Class: Numo::NArray

Inherits:
Object
  • Object
show all
Defined in:
ext/numo/narray/narray.c,
ext/numo/narray/narray.c,
lib/numo/narray/extra.rb

Overview

Numo::NArray is the abstract super class for Numerical N-dimensional Array in the Ruby/Numo module. Use Typed Subclasses of NArray (Numo::DFloat, Int32, etc) to create data array instances.

Defined Under Namespace

Classes: CastError, DimensionError, OperationError, ShapeError

Constant Summary

VERSION =
rb_str_new2(NARRAY_VERSION)
@@warn_slow_dot =
false

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(shape) ⇒ Numo::NArray #initialize(size0, size1, ...) ⇒ Numo::NArray

Constructs an instance of NArray class using the given and shape or sizes. Note that NArray itself is an abstract super class and not suitable to create instances. Use Typed Subclasses of NArray (DFloat, Int32, etc) to create instances. This method does not allocate memory for array data. Memory is allocated on write method such as #fill, #store, #seq, etc.

Examples:

i = Numo::Int64.new([2,4,3])
#=> Numo::Int64#shape=[2,4,3](empty)

f = Numo::DFloat.new(3,4)
#=> Numo::DFloat#shape=[3,4](empty)

f.fill(2)
#=> Numo::DFloat#shape=[3,4]
# [[2, 2, 2, 2],
#  [2, 2, 2, 2],
#  [2, 2, 2, 2]]

x = Numo::NArray.new(5)
#=> in `new': allocator undefined for Numo::NArray (TypeError)
#   	from t.rb:9:in `<main>'

Parameters:

  • shape (Array)

    (array of sizes along each dimension)

  • sizeN (Integer)

    (size along Nth-dimension)



366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
# File 'ext/numo/narray/narray.c', line 366

static VALUE
na_initialize(VALUE self, VALUE args)
{
    VALUE v;
    size_t *shape=NULL;
    int ndim;

    if (RARRAY_LEN(args) == 1) {
        v = RARRAY_AREF(args,0);
        if (TYPE(v) != T_ARRAY) {
            v = args;
        }
    } else {
        v = args;
    }
    ndim = RARRAY_LEN(v);
    if (ndim > NA_MAX_DIMENSION) {
        rb_raise(rb_eArgError,"ndim=%d exceeds maximum dimension",ndim);
    }
    shape = ALLOCA_N(size_t, ndim);
    // setup size_t shape[] from VALUE shape argument
    na_array_to_internal_shape(self, v, shape);
    na_setup(self, ndim, shape);

    return self;
}

Class Method Details

.[](elements) ⇒ NArray

Generate NArray object. NArray datatype is automatically selected.

Parameters:

  • elements (Numeric, Array)

Returns:



505
506
507
508
509
510
511
512
513
514
515
516
# File 'ext/numo/narray/array.c', line 505

static VALUE
nary_s_bracket(VALUE klass, VALUE ary)
{
    VALUE dtype=Qnil;

    if (TYPE(ary)!=T_ARRAY) {
        rb_bug("Argument is not array");
    }
    dtype = na_ary_composition_dtype(ary);
    check_subclass_of_narray(dtype);
    return rb_funcall(dtype, id_cast, 1, ary);
}

.array_type(ary) ⇒ Object



492
493
494
495
496
# File 'ext/numo/narray/array.c', line 492

static VALUE
na_s_array_type(VALUE mod, VALUE ary)
{
    return na_ary_composition_dtype(ary);
}

.asarray(a) ⇒ Object



162
163
164
165
166
167
168
169
170
171
# File 'lib/numo/narray/extra.rb', line 162

def self.asarray(a)
  case a
  when NArray
    (a.ndim == 0) ? a[:new] : a
  when Numeric,Range
    self[a]
  else
    cast(a)
  end
end

.byte_sizeNumeric

Returns byte size of one element of NArray.

Returns:

  • (Numeric)

    byte size.



1179
1180
1181
1182
1183
# File 'ext/numo/narray/narray.c', line 1179

static VALUE
nary_s_byte_size(VALUE type)
{
    return rb_const_get(type, id_element_byte_size);
}

.cast(a) ⇒ Object

Convert the argument to an narray if not an narray.



158
159
160
# File 'lib/numo/narray/extra.rb', line 158

def self.cast(a)
  a.kind_of?(NArray) ? a : NArray.array_type(a).cast(a)
end

.column_stack(arrays) ⇒ Object

Stack 1-d arrays into columns of a 2-d array.

Examples:

x = Numo::Int32[1,2,3]
y = Numo::Int32[2,3,4]
p Numo::NArray.column_stack([x,y])
# Numo::Int32#shape=[3,2]
# [[1, 2],
#  [2, 3],
#  [3, 4]]


559
560
561
562
563
564
565
566
567
568
569
# File 'lib/numo/narray/extra.rb', line 559

def column_stack(arrays)
  arys = arrays.map do |a|
    a = cast(a)
    case a.ndim
    when 0; a[:new,:new]
    when 1; a[true,:new]
    else; a
    end
  end
  concatenate(arys,axis:1)
end

.concatenate(arrays, axis: 0) ⇒ Object

Examples:

p a = Numo::DFloat[[1, 2], [3, 4]]
# Numo::DFloat#shape=[2,2]
# [[1, 2],
#  [3, 4]]

p b = Numo::DFloat[[5, 6]]
# Numo::DFloat#shape=[1,2]
# [[5, 6]]

p Numo::NArray.concatenate([a,b],axis:0)
# Numo::DFloat#shape=[3,2]
# [[1, 2],
#  [3, 4],
#  [5, 6]]

p Numo::NArray.concatenate([a,b.transpose], axis:1)
# Numo::DFloat#shape=[2,3]
# [[1, 2, 5],
#  [3, 4, 6]]


415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
# File 'lib/numo/narray/extra.rb', line 415

def concatenate(arrays,axis:0)
  klass = (self==NArray) ? NArray.array_type(arrays) : self
  nd = 0
  arrays = arrays.map do |a|
    case a
    when NArray
      # ok
    when Numeric
      a = klass[a]
    when Array
      a = klass.cast(a)
    else
      raise TypeError,"not Numo::NArray: #{a.inspect[0..48]}"
    end
    if a.ndim > nd
      nd = a.ndim
    end
    a
  end
  if axis < 0
    axis += nd
  end
  if axis < 0 || axis >= nd
    raise ArgumentError,"axis is out of range"
  end
  new_shape = nil
  sum_size = 0
  arrays.each do |a|
    a_shape = a.shape
    if nd != a_shape.size
      a_shape = [1]*(nd-a_shape.size) + a_shape
    end
    sum_size += a_shape.delete_at(axis)
    if new_shape
      if new_shape != a_shape
        raise ShapeError,"shape mismatch"
      end
    else
      new_shape = a_shape
    end
  end
  new_shape.insert(axis,sum_size)
  result = klass.zeros(*new_shape)
  lst = 0
  refs = [true] * nd
  arrays.each do |a|
    fst = lst
    lst = fst + (a.shape[axis-nd]||1)
    refs[axis] = fst...lst
    result[*refs] = a
  end
  result
end

.debug=(flag) ⇒ Object



1711
1712
1713
1714
1715
# File 'ext/numo/narray/narray.c', line 1711

static VALUE na_debug_set(VALUE mod, VALUE flag)
{
    na_debug_flag = RTEST(flag);
    return Qnil;
}

.diag_indices(m, n, k = 0) ⇒ Object

Return the k-th diagonal indices.



1049
1050
1051
1052
1053
# File 'lib/numo/narray/extra.rb', line 1049

def self.diag_indices(m,n,k=0)
  x = Numo::Int64.new(m,1).seq + k
  y = Numo::Int64.new(1,n).seq
  (x.eq y).where
end

.dstack(arrays) ⇒ Object

Stack arrays in depth wise (along third axis).

Examples:

a = Numo::Int32[1,2,3]
b = Numo::Int32[2,3,4]
p Numo::NArray.dstack([a,b])
# Numo::Int32#shape=[1,3,2]
# [[[1, 2],
#   [2, 3],
#   [3, 4]]]

a = Numo::Int32[[1],[2],[3]]
b = Numo::Int32[[2],[3],[4]]
p Numo::NArray.dstack([a,b])
# Numo::Int32#shape=[3,1,2]
# [[[1, 2]],
#  [[2, 3]],
#  [[3, 4]]]


542
543
544
545
546
547
# File 'lib/numo/narray/extra.rb', line 542

def dstack(arrays)
  arys = arrays.map do |a|
    _atleast_3d(cast(a))
  end
  concatenate(arys,axis:2)
end

.eye(n) ⇒ Numo::NArray

Returns a NArray with shape=(n,n) whose diagonal elements are 1, otherwise 0.

Examples:

a = Numo::DFloat.eye(3)
=> Numo::DFloat#shape=[3,3]
[[1, 0, 0],
 [0, 1, 0],
 [0, 0, 1]]

Parameters:

  • n (Integer)

    Size of NArray. Creates 2-D NArray with shape=(n,n)

Returns:



579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
# File 'ext/numo/narray/narray.c', line 579

static VALUE
na_s_eye(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj;
    VALUE tmp[2];

    if (argc==0) {
        rb_raise(rb_eArgError,"No argument");
    }
    else if (argc==1) {
        tmp[0] = tmp[1] = argv[0];
        argv = tmp;
        argc = 2;
    }
    obj = rb_class_new_instance(argc, argv, klass);
    return rb_funcall(obj, id_eye, 0);
}

.from_binary(string, [shape]) ⇒ Numo::NArray

Returns a new 1-D array initialized from binary raw data in a string.

Parameters:

  • string (String)

    Binary raw data.

  • shape (Array)

    array of integers representing array shape.

Returns:



1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
# File 'ext/numo/narray/narray.c', line 1193

static VALUE
nary_s_from_binary(int argc, VALUE *argv, VALUE type)
{
    size_t len, str_len, byte_size;
    size_t *shape;
    char *ptr;
    int   i, nd, narg;
    VALUE vstr, vshape, vna;
    VALUE velmsz;

    narg = rb_scan_args(argc,argv,"11",&vstr,&vshape);
    Check_Type(vstr,T_STRING);
    str_len = RSTRING_LEN(vstr);
    velmsz = rb_const_get(type, id_element_byte_size);
    if (narg==2) {
        switch(TYPE(vshape)) {
        case T_FIXNUM:
            nd = 1;
            len = NUM2SIZET(vshape);
            shape = &len;
            break;
        case T_ARRAY:
            nd = RARRAY_LEN(vshape);
            if (nd == 0 || nd > NA_MAX_DIMENSION) {
                rb_raise(nary_eDimensionError,"too long or empty shape (%d)", nd);
            }
            shape = ALLOCA_N(size_t,nd);
            len = 1;
            for (i=0; i<nd; ++i) {
                len *= shape[i] = NUM2SIZET(RARRAY_AREF(vshape,i));
            }
            break;
        default:
            rb_raise(rb_eArgError,"second argument must be size or shape");
        }
        if (FIXNUM_P(velmsz)) {
            byte_size = len * NUM2SIZET(velmsz);
        } else {
            byte_size = ceil(len * NUM2DBL(velmsz));
        }
        if (byte_size > str_len) {
            rb_raise(rb_eArgError, "specified size is too large");
        }
    } else {
        nd = 1;
        if (FIXNUM_P(velmsz)) {
            len = str_len / NUM2SIZET(velmsz);
            byte_size = len * NUM2SIZET(velmsz);
        } else {
            len = floor(str_len / NUM2DBL(velmsz));
            byte_size = str_len;
        }
        if (len == 0) {
            rb_raise(rb_eArgError, "string is empty or too short");
        }
        shape = ALLOCA_N(size_t,nd);
        shape[0] = len;
    }

    vna = nary_new(type, nd, shape);
    ptr = na_get_pointer_for_write(vna);

    memcpy(ptr, RSTRING_PTR(vstr), byte_size);

    return vna;
}

.hstack(arrays) ⇒ Object

Stack arrays horizontally (column wise).

Examples:

a = Numo::Int32[1,2,3]
b = Numo::Int32[2,3,4]
p Numo::NArray.hstack([a,b])
# Numo::Int32#shape=[6]
# [1, 2, 3, 2, 3, 4]

a = Numo::Int32[[1],[2],[3]]
b = Numo::Int32[[2],[3],[4]]
p Numo::NArray.hstack([a,b])
# Numo::Int32#shape=[3,2]
# [[1, 2],
#  [2, 3],
#  [3, 4]]


512
513
514
515
516
517
518
519
520
521
522
# File 'lib/numo/narray/extra.rb', line 512

def hstack(arrays)
  klass = (self==NArray) ? NArray.array_type(arrays) : self
  nd = 0
  arys = arrays.map do |a|
    a = klass.cast(a)
    nd = a.ndim if a.ndim > nd
    a
  end
  dim = (nd >= 2) ? 1 : 0
  concatenate(arys,axis:dim)
end

.inspect_colsInteger or nil

Returns the number of cols used for NArray#inspect

Returns:

  • (Integer or nil)

    the number of cols.



1766
1767
1768
1769
1770
1771
1772
1773
# File 'ext/numo/narray/narray.c', line 1766

static VALUE na_inspect_cols(VALUE mod)
{
    if (numo_na_inspect_cols > 0) {
        return INT2NUM(numo_na_inspect_cols);
    } else {
        return Qnil;
    }
}

.inspect_cols=(cols) ⇒ nil

Set the number of cols used for NArray#inspect

Parameters:

  • cols (Integer or nil)

    the number of cols

Returns:

  • (nil)


1781
1782
1783
1784
1785
1786
1787
1788
1789
# File 'ext/numo/narray/narray.c', line 1781

static VALUE na_inspect_cols_set(VALUE mod, VALUE num)
{
    if (RTEST(num)) {
        numo_na_inspect_cols = NUM2INT(num);
    } else {
        numo_na_inspect_cols = 0;
    }
    return Qnil;
}

.inspect_rowsInteger or nil

Returns the number of rows used for NArray#inspect

Returns:

  • (Integer or nil)

    the number of rows.



1736
1737
1738
1739
1740
1741
1742
1743
# File 'ext/numo/narray/narray.c', line 1736

static VALUE na_inspect_rows(VALUE mod)
{
    if (numo_na_inspect_rows > 0) {
        return INT2NUM(numo_na_inspect_rows);
    } else {
        return Qnil;
    }
}

.inspect_rows=(rows) ⇒ nil

Set the number of rows used for NArray#inspect

Parameters:

  • rows (Integer or nil)

    the number of rows

Returns:

  • (nil)


1751
1752
1753
1754
1755
1756
1757
1758
1759
# File 'ext/numo/narray/narray.c', line 1751

static VALUE na_inspect_rows_set(VALUE mod, VALUE num)
{
    if (RTEST(num)) {
        numo_na_inspect_rows = NUM2INT(num);
    } else {
        numo_na_inspect_rows = 0;
    }
    return Qnil;
}

.linspace(x1, x2, [n]) ⇒ Numo::NArray

Returns an array of N linearly spaced points between x1 and x2. This singleton method is valid not for NArray class itself but for typed NArray subclasses, e.g., DFloat, Int64.

Examples:

a = Numo::DFloat.linspace(-5,5,7)
=> Numo::DFloat#shape=[7]
[-5, -3.33333, -1.66667, 0, 1.66667, 3.33333, 5]

Parameters:

  • x1 (Numeric)

    The start value

  • x2 (Numeric)

    The end value

  • n (Integer)

    The number of elements. (default is 100).

Returns:



500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
# File 'ext/numo/narray/narray.c', line 500

static VALUE
na_s_linspace(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj, vx1, vx2, vstep, vsize;
    double n;
    int narg;

    narg = rb_scan_args(argc,argv,"21",&vx1,&vx2,&vsize);
    if (narg==3) {
        n = NUM2DBL(vsize);
    } else {
        n = 100;
        vsize = INT2FIX(100);
    }

    obj = rb_funcall(vx2, '-', 1, vx1);
    vstep = rb_funcall(obj, '/', 1, DBL2NUM(n-1));

    obj = rb_class_new_instance(1, &vsize, klass);
    return rb_funcall(obj, id_seq, 2, vx1, vstep);
}

.logspace(a, b, [n, base]) ⇒ Numo::NArray

Returns an array of N logarithmically spaced points between 10^a and 10^b. This singleton method is valid not for NArray having logseq method, i.e., DFloat, SFloat, DComplex, and SComplex.

Examples:

Numo::DFloat.logspace(4,0,5,2)
=> Numo::DFloat#shape=[5]
   [16, 8, 4, 2, 1]
Numo::DComplex.logspace(0,1i*Math::PI,5,Math::E)
=> Numo::DComplex#shape=[5]
   [1+4.44659e-323i, 0.707107+0.707107i, 6.12323e-17+1i, -0.707107+0.707107i, ...]

Parameters:

  • a (Numeric)

    The start value

  • b (Numeric)

    The end value

  • n (Integer)

    The number of elements. (default is 50)

  • base (Numeric)

    The base of log space. (default is 10)

Returns:



542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
# File 'ext/numo/narray/narray.c', line 542

static VALUE
na_s_logspace(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj, vx1, vx2, vstep, vsize, vbase;
    double n;

    rb_scan_args(argc,argv,"22",&vx1,&vx2,&vsize,&vbase);
    if (vsize == Qnil) {
        vsize = INT2FIX(50);
        n = 50;
    } else {
        n = NUM2DBL(vsize);
    }
    if (vbase == Qnil) {
        vbase = DBL2NUM(10);
    }

    obj = rb_funcall(vx2, '-', 1, vx1);
    vstep = rb_funcall(obj, '/', 1, DBL2NUM(n-1));

    obj = rb_class_new_instance(1, &vsize, klass);
    return rb_funcall(obj, id_logseq, 3, vx1, vstep, vbase);
}

.new_like(obj) ⇒ Numo::NArray

Generate new unallocated NArray instance with shape and type defined from obj. Numo::NArray.new_like(obj) returns instance whose type is defined from obj. Numo::DFloat.new_like(obj) returns DFloat instance.

Examples:

Numo::NArray.new_like([[1,2,3],[4,5,6]])
=> Numo::Int32#shape=[2,3](empty)
Numo::DFloat.new_like([[1,2],[3,4]])
=> Numo::DFloat#shape=[2,2](empty)
Numo::NArray.new_like([1,2i,3])
=> Numo::DComplex#shape=[3](empty)

Parameters:

Returns:



473
474
475
476
477
478
479
480
# File 'ext/numo/narray/array.c', line 473

VALUE
na_s_new_like(VALUE type, VALUE obj)
{
    VALUE newary;

    na_composition3(obj, &type, 0, &newary);
    return newary;
}

.ones(shape) ⇒ Object .ones(size1, size2, ...) ⇒ Object

Returns a one-filled narray with shape. This singleton method is valid not for NArray class itself but for typed NArray subclasses, e.g., DFloat, Int64.

Examples:

a = Numo::DFloat.ones(3,5)
=> Numo::DFloat#shape=[3,5]
[[1, 1, 1, 1, 1],
 [1, 1, 1, 1, 1],
 [1, 1, 1, 1, 1]]


475
476
477
478
479
480
481
# File 'ext/numo/narray/narray.c', line 475

static VALUE
na_s_ones(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj;
    obj = rb_class_new_instance(argc, argv, klass);
    return rb_funcall(obj, id_fill, 1, INT2FIX(1));
}

.parse(str, split1d: /\s+/, split2d: /;?$|;/, split3d: /\s*\n(\s*\n)+/m) ⇒ Object

parse matrix like matlab, octave

Examples:

a = Numo::DFloat.parse %[
 2 -3 5
 4 9 7
 2 -1 6
]
=> Numo::DFloat#shape=[3,3]
[[2, -3, 5],
 [4, 9, 7],
 [2, -1, 6]]


185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
# File 'lib/numo/narray/extra.rb', line 185

def self.parse(str, split1d:/\s+/, split2d:/;?$|;/,
               split3d:/\s*\n(\s*\n)+/m)
  a = []
  str.split(split3d).each do |block|
    b = []
    #print "b"; p block
    block.split(split2d).each do |line|
      #p line
      line.strip!
      if !line.empty?
        c = []
        line.split(split1d).each do |item|
          c << eval(item.strip) if !item.empty?
        end
        b << c if !c.empty?
      end
    end
    a << b if !b.empty?
  end
  if a.size==1
    self.cast(a[0])
  else
    self.cast(a)
  end
end

.profileObject



1719
1720
1721
1722
# File 'ext/numo/narray/narray.c', line 1719

static VALUE na_profile(VALUE mod)
{
    return rb_float_new(na_profile_value);
}

.profile=(val) ⇒ Object



1724
1725
1726
1727
1728
# File 'ext/numo/narray/narray.c', line 1724

static VALUE na_profile_set(VALUE mod, VALUE val)
{
    na_profile_value = NUM2DBL(val);
    return val;
}

.srand(*args) ⇒ Object



50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
# File 'ext/numo/narray/rand.c', line 50

static VALUE
 nary_s_srand(int argc, VALUE *argv, VALUE obj)
{
    VALUE vseed;
    u_int64_t seed;

    //rb_secure(4);
    if (rb_scan_args(argc, argv, "01", &vseed) == 0) {
        seed = random_seed();
    }
    else {
        seed = NUM2UINT64(vseed);
    }
    init_gen_rand(seed);

    return Qnil;
}

.tril_indices(m, n, k = 0) ⇒ Object

Return the indices for the lower-triangle on and below the k-th diagonal.



1033
1034
1035
1036
1037
# File 'lib/numo/narray/extra.rb', line 1033

def self.tril_indices(m,n,k=0)
  x = Numo::Int64.new(m,1).seq + k
  y = Numo::Int64.new(1,n).seq
  (x>=y).where
end

.triu_indices(m, n, k = 0) ⇒ Object

Return the indices for the uppler-triangle on and above the k-th diagonal.



994
995
996
997
998
# File 'lib/numo/narray/extra.rb', line 994

def self.triu_indices(m,n,k=0)
  x = Numo::Int64.new(m,1).seq + k
  y = Numo::Int64.new(1,n).seq
  (x<=y).where
end

.upcast(type2) ⇒ Object




1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
# File 'ext/numo/narray/narray.c', line 1115

VALUE
numo_na_upcast(VALUE type1, VALUE type2)
{
    VALUE upcast_hash;
    VALUE result_type;

    if (type1==type2) {
        return type1;
    }
    upcast_hash = rb_const_get(type1, id_UPCAST);
    result_type = rb_hash_aref(upcast_hash, type2);
    if (NIL_P(result_type)) {
        if (TYPE(type2)==T_CLASS) {
            if (RTEST(rb_class_inherited_p(type2,cNArray))) {
                upcast_hash = rb_const_get(type2, id_UPCAST);
                result_type = rb_hash_aref(upcast_hash, type1);
            }
        }
    }
    return result_type;
}

.vstack(arrays) ⇒ Object

Stack arrays vertically (row wise).

Examples:

a = Numo::Int32[1,2,3]
b = Numo::Int32[2,3,4]
p Numo::NArray.vstack([a,b])
# Numo::Int32#shape=[2,3]
# [[1, 2, 3],
#  [2, 3, 4]]

a = Numo::Int32[[1],[2],[3]]
b = Numo::Int32[[2],[3],[4]]
p Numo::NArray.vstack([a,b])
# Numo::Int32#shape=[6,1]
# [[1],
#  [2],
#  [3],
#  [2],
#  [3],
#  [4]]


489
490
491
492
493
494
# File 'lib/numo/narray/extra.rb', line 489

def vstack(arrays)
  arys = arrays.map do |a|
    _atleast_2d(cast(a))
  end
  concatenate(arys,axis:0)
end

.zeros(shape) ⇒ Object .zeros(size1, size2, ...) ⇒ Object

Returns a zero-filled narray with shape. This singleton method is valid not for NArray class itself but for typed NArray subclasses, e.g., DFloat, Int64.

Examples:

a = Numo::DFloat.zeros(3,5)
=> Numo::DFloat#shape=[3,5]
[[0, 0, 0, 0, 0],
 [0, 0, 0, 0, 0],
 [0, 0, 0, 0, 0]]


451
452
453
454
455
456
457
# File 'ext/numo/narray/narray.c', line 451

static VALUE
na_s_zeros(int argc, VALUE *argv, VALUE klass)
{
    VALUE obj;
    obj = rb_class_new_instance(argc, argv, klass);
    return rb_funcall(obj, id_fill, 1, INT2FIX(0));
}

Instance Method Details

#==(other) ⇒ Boolean

Equality of self and other in view of numerical array. i.e., both arrays have same shape and corresponding elements are equal.

Parameters:

  • other (Object)

Returns:

  • (Boolean)

    true if self and other is equal.



1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
# File 'ext/numo/narray/narray.c', line 1799

VALUE
na_equal(VALUE self, volatile VALUE other)
{
    volatile VALUE vbool;
    narray_t *na1, *na2;
    int i;

    GetNArray(self,na1);

    if (!rb_obj_is_kind_of(other,cNArray)) {
        other = rb_funcall(CLASS_OF(self), id_cast, 1, other);
    }

    GetNArray(other,na2);
    if (na1->ndim != na2->ndim) {
        return Qfalse;
    }
    for (i=0; i<na1->ndim; i++) {
        if (na1->shape[i] != na2->shape[i]) {
            return Qfalse;
        }
    }
    vbool = rb_funcall(self, id_eq, 1, other);
    return (rb_funcall(vbool, id_count_false, 0)==INT2FIX(0)) ? Qtrue : Qfalse;
}

#append(other, axis: nil) ⇒ Object

Append values to the end of an narray.

Examples:

a = Numo::DFloat[1, 2, 3]
p a.append([[4, 5, 6], [7, 8, 9]])
# Numo::DFloat#shape=[9]
# [1, 2, 3, 4, 5, 6, 7, 8, 9]

a = Numo::DFloat[[1, 2, 3]]
p a.append([[4, 5, 6], [7, 8, 9]],axis:0)
# Numo::DFloat#shape=[3,3]
# [[1, 2, 3],
#  [4, 5, 6],
#  [7, 8, 9]]

a = Numo::DFloat[[1, 2, 3], [4, 5, 6]]
p a.append([7, 8, 9], axis:0)
# in `append': dimension mismatch (Numo::NArray::DimensionError)


229
230
231
232
233
234
235
236
237
238
239
240
241
242
# File 'lib/numo/narray/extra.rb', line 229

def append(other,axis:nil)
  other = self.class.cast(other)
  if axis
    if ndim != other.ndim
      raise DimensionError, "dimension mismatch"
    end
    return concatenate(other,axis:axis)
  else
    a = self.class.zeros(size+other.size)
    a[0...size] = self[true]
    a[size..-1] = other[true]
    return a
  end
end

#at(*indices) ⇒ Numo::NArray

Multi-dimensional array indexing. Same as [] for one-dimensional NArray. Similar to numpy's tuple indexing, i.e., a[[1,2,..],[3,4,..]] (This method will be rewritten in C)

Examples:

p x = Numo::DFloat.new(3,3,3).seq
# Numo::DFloat#shape=[3,3,3]
# [[[0, 1, 2],
#   [3, 4, 5],
#   [6, 7, 8]],
#  [[9, 10, 11],
#   [12, 13, 14],
#   [15, 16, 17]],
#  [[18, 19, 20],
#   [21, 22, 23],
#   [24, 25, 26]]]

p x.at([0,1,2],[0,1,2],[-1,-2,-3])
# Numo::DFloat(view)#shape=[3]
# [2, 13, 24]

Returns:



67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
# File 'lib/numo/narray/extra.rb', line 67

def at(*indices)
  if indices.size != ndim
    raise DimensionError, "argument length does not match dimension size"
  end
  idx = nil
  stride = 1
  (indices.size-1).downto(0) do |i|
    ix = Int64.cast(indices[i])
    if ix.ndim != 1
      raise DimensionError, "index array is not one-dimensional"
    end
    ix[ix < 0] += shape[i]
    if ((ix < 0) & (ix >= shape[i])).any?
      raise IndexError, "index array is out of range"
    end
    if idx
      if idx.size != ix.size
        raise ShapeError, "index array sizes mismatch"
      end
      idx += ix * stride
      stride *= shape[i]
    else
      idx = ix
      stride = shape[i]
    end
  end
  self[idx]
end

#byte_sizeInteger

Returns total byte size of NArray.

Returns:

  • (Integer)

    byte size.



1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
# File 'ext/numo/narray/narray.c', line 1161

static VALUE
nary_byte_size(VALUE self)
{
    VALUE velmsz;
    narray_t *na;

    GetNArray(self,na);
    velmsz = rb_const_get(CLASS_OF(self), id_element_byte_size);
    if (FIXNUM_P(velmsz)) {
        return SIZET2NUM(NUM2SIZET(velmsz) * na->size);
    }
    return SIZET2NUM(ceil(NUM2DBL(velmsz) * na->size));
}

#byte_swapped?Boolean Also known as: network_order?

Return true if byte swapped.

Returns:

  • (Boolean)


1640
1641
1642
1643
1644
1645
# File 'ext/numo/narray/narray.c', line 1640

VALUE na_byte_swapped_p( VALUE self )
{
    if (TEST_BYTE_SWAPPED(self))
      return Qtrue;
    return Qfalse;
}

#cast_to(datatype) ⇒ Numo::NArray

Cast self to another NArray datatype.

Parameters:

  • datatype (Class)

    NArray datatype.

Returns:



1425
1426
1427
1428
1429
# File 'ext/numo/narray/narray.c', line 1425

static VALUE
nary_cast_to(VALUE obj, VALUE type)
{
    return rb_funcall(type, id_cast, 1, obj);
}

#coerce(other) ⇒ Array

Returns an array containing other and self, both are converted to upcasted type of NArray. Note that NArray has distinct UPCAST mechanism. Coerce is used for operation between non-NArray and NArray.

Parameters:

  • other (Object)

    numeric object.

Returns:

  • (Array)

    NArray-casted [other,self]



1146
1147
1148
1149
1150
1151
1152
1153
1154
# File 'ext/numo/narray/narray.c', line 1146

static VALUE
nary_coerce(VALUE x, VALUE y)
{
    VALUE type;

    type = numo_na_upcast(CLASS_OF(x), CLASS_OF(y));
    y = rb_funcall(type,id_cast,1,y);
    return rb_assoc_new(y , x);
}

#column_major?Boolean

Return true if column major.

Returns:

  • (Boolean)


1617
1618
1619
1620
1621
1622
1623
# File 'ext/numo/narray/narray.c', line 1617

VALUE na_column_major_p( VALUE self )
{
    if (TEST_COLUMN_MAJOR(self))
	return Qtrue;
    else
	return Qfalse;
}

#concatenate(*arrays, axis: 0) ⇒ Object

Examples:

p a = Numo::DFloat[[1, 2], [3, 4]]
# Numo::DFloat#shape=[2,2]
# [[1, 2],
#  [3, 4]]

p b = Numo::DFloat[[5, 6]]
# Numo::DFloat#shape=[1,2]
# [[5, 6]]

p a.concatenate(b,axis:0)
# Numo::DFloat#shape=[3,2]
# [[1, 2],
#  [3, 4],
#  [5, 6]]

p a.concatenate(b.transpose, axis:1)
# Numo::DFloat#shape=[2,3]
# [[1, 2, 5],
#  [3, 4, 6]]


614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
# File 'lib/numo/narray/extra.rb', line 614

def concatenate(*arrays,axis:0)
  axis = check_axis(axis)
  self_shape = shape
  self_shape.delete_at(axis)
  sum_size = shape[axis]
  arrays.map! do |a|
    case a
    when NArray
      # ok
    when Numeric
      a = self.class.new(1).store(a)
    when Array
      a = self.class.cast(a)
    else
      raise TypeError,"not Numo::NArray: #{a.inspect[0..48]}"
    end
    if a.ndim > ndim
      raise ShapeError,"dimension mismatch"
    end
    a_shape = a.shape
    sum_size += a_shape.delete_at(axis-ndim) || 1
    if self_shape != a_shape
      raise ShapeError,"shape mismatch"
    end
    a
  end
  self_shape.insert(axis,sum_size)
  result = self.class.zeros(*self_shape)
  lst = shape[axis]
  refs = [true] * ndim
  refs[axis] = 0...lst
  result[*refs] = self
  arrays.each do |a|
    fst = lst
    lst = fst + (a.shape[axis-ndim] || 1)
    refs[axis] = fst...lst
    result[*refs] = a
  end
  result
end

#contiguous?Boolean

Returns:

  • (Boolean)


873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
# File 'ext/numo/narray/narray.c', line 873

VALUE
na_check_contiguous(VALUE self)
{
    ssize_t elmsz;
    narray_t *na;
    GetNArray(self,na);

    switch(na->type) {
    case NARRAY_DATA_T:
    case NARRAY_FILEMAP_T:
        return Qtrue;
    case NARRAY_VIEW_T:
        if (NA_VIEW_STRIDX(na)==0) {
            return Qtrue;
        }
        if (na_check_ladder(self,0)==Qtrue) {
            elmsz = nary_element_stride(self);
            if (elmsz == NA_STRIDE_AT(na,NA_NDIM(na)-1)) {
                return Qtrue;
            }
        }
    }
    return Qfalse;
}

#cov(y = nil, ddof: 1, fweights: nil, aweights: nil) ⇒ Object

under construction



1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
# File 'lib/numo/narray/extra.rb', line 1202

def cov(y=nil, ddof:1, fweights:nil, aweights:nil)
  if y
    m = NArray.vstack([self,y])
  else
    m = self
  end
  w = nil
  if fweights
    f = fweights
    w = f
  end
  if aweights
    a = aweights
    w = w ? w*a : a
  end
  if w
    w_sum = w.sum(axis:-1, keepdims:true)
    if ddof == 0
      fact = w_sum
    elsif aweights.nil?
      fact = w_sum - ddof
    else
      wa_sum = (w*a).sum(axis:-1, keepdims:true)
      fact = w_sum - ddof * wa_sum / w_sum
    end
    if (fact <= 0).any?
      raise StandardError,"Degrees of freedom <= 0 for slice"
    end
  else
    fact = m.shape[-1] - ddof
  end
  if w
    m -= (m*w).sum(axis:-1, keepdims:true) / w_sum
    mw = m*w
  else
    m -= m.mean(axis:-1, keepdims:true)
    mw = m
  end
  mt = (m.ndim < 2) ? m : m.swapaxes(-2,-1)
  mw.dot(mt.conj) / fact
end

#debug_infoObject



127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
# File 'ext/numo/narray/narray.c', line 127

VALUE
nary_debug_info(VALUE self)
{
    int i;
    narray_t *na;
    GetNArray(self,na);

    printf("%s:\n",rb_class2name(CLASS_OF(self)));
    printf("  id     = 0x%"PRI_VALUE_PREFIX"x\n", self);
    printf("  type   = %d\n", na->type);
    printf("  flag   = [%d,%d]\n", na->flag[0], na->flag[1]);
    printf("  size   = %"SZF"d\n", na->size);
    printf("  ndim   = %d\n", na->ndim);
    printf("  shape  = 0x%"SZF"x\n", (size_t)na->shape);
    if (na->shape) {
        printf("  shape  = [");
        for (i=0;i<na->ndim;i++)
            printf(" %"SZF"d", na->shape[i]);
        printf(" ]\n");
    }

    switch(na->type) {
    case NARRAY_DATA_T:
    case NARRAY_FILEMAP_T:
        nary_debug_info_nadata(self);
        break;
    case NARRAY_VIEW_T:
        nary_debug_info_naview(self);
        break;
    }
    return Qnil;
}

#deg2radObject

Convert angles from degrees to radians.



30
31
32
# File 'lib/numo/narray/extra.rb', line 30

def deg2rad
  self * (Math::PI/180)
end

#delete(indice, axis = nil) ⇒ Object

Examples:

a = Numo::DFloat[[1,2,3,4], [5,6,7,8], [9,10,11,12]]
p a.delete(1,0)
# Numo::DFloat(view)#shape=[2,4]
# [[1, 2, 3, 4],
#  [9, 10, 11, 12]]

p a.delete((0..-1).step(2),1)
# Numo::DFloat(view)#shape=[3,2]
# [[2, 4],
#  [6, 8],
#  [10, 12]]

p a.delete([1,3,5])
# Numo::DFloat(view)#shape=[9]
# [1, 3, 5, 7, 8, 9, 10, 11, 12]


264
265
266
267
268
269
270
271
272
273
274
275
276
# File 'lib/numo/narray/extra.rb', line 264

def delete(indice,axis=nil)
  if axis
    bit = Bit.ones(shape[axis])
    bit[indice] = 0
    idx = [true]*ndim
    idx[axis] = bit.where
    return self[*idx].copy
  else
    bit = Bit.ones(size)
    bit[indice] = 0
    return self[bit.where].copy
  end
end

#diag(k = 0) ⇒ Object

Return a matrix whose diagonal is constructed by self along the last axis.



1056
1057
1058
1059
1060
1061
1062
# File 'lib/numo/narray/extra.rb', line 1056

def diag(k=0)
  *shp,n = shape
  n += k.abs
  a = self.class.zeros(*shp,n,n)
  a.diagonal(k).store(self)
  a
end

#diag_indices(k = 0) ⇒ Object

Return the k-th diagonal indices.



1040
1041
1042
1043
1044
1045
1046
# File 'lib/numo/narray/extra.rb', line 1040

def diag_indices(k=0)
  if ndim < 2
    raise NArray::ShapeError, "must be >= 2-dimensional array"
  end
  m,n = shape[-2..-1]
  NArray.diag_indices(m,n,k)
end

#diagonal([offset,axes]) ⇒ Numo::NArray

Returns a diagonal view of NArray

Examples:

a = Numo::DFloat.new(4,5).seq
=> Numo::DFloat#shape=[4,5]
[[0, 1, 2, 3, 4],
 [5, 6, 7, 8, 9],
 [10, 11, 12, 13, 14],
 [15, 16, 17, 18, 19]]
b = a.diagonal(1)
=> Numo::DFloat(view)#shape=[4]
[1, 7, 13, 19]
b.store(0)
a
=> Numo::DFloat#shape=[4,5]
[[0, 0, 2, 3, 4],
 [5, 6, 0, 8, 9],
 [10, 11, 12, 0, 14],
 [15, 16, 17, 18, 0]]
b.store([1,2,3,4])
a
=> Numo::DFloat#shape=[4,5]
[[0, 1, 2, 3, 4],
 [5, 6, 2, 8, 9],
 [10, 11, 12, 3, 14],
 [15, 16, 17, 18, 4]]

Parameters:

  • offset (Integer)

    Diagonal offset from the main diagonal. The default is 0. k>0 for diagonals above the main diagonal, and k<0 for diagonals below the main diagonal.

  • axes (Array)

    Array of axes to be used as the 2-d sub-arrays from which the diagonals should be taken. Defaults to last-two axes ([-2,-1]).

Returns:



594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
# File 'ext/numo/narray/data.c', line 594

VALUE
na_diagonal(int argc, VALUE *argv, VALUE self)
{
    int  i, k, nd;
    size_t  j;
    size_t *idx0, *idx1, *diag_idx;
    size_t *shape;
    size_t  diag_size;
    ssize_t stride, stride0, stride1;
    narray_t *na;
    narray_view_t *na1, *na2;
    VALUE view;
    VALUE vofs=0, vaxes=0;
    ssize_t kofs;
    size_t k0, k1;
    int ax[2];

    // check arguments
    if (argc>2) {
        rb_raise(rb_eArgError,"too many arguments (%d for 0..2)",argc);
    }

    for (i=0; i<argc; i++) {
        switch(TYPE(argv[i])) {
        case T_FIXNUM:
            if (vofs) {
                rb_raise(rb_eArgError,"offset is given twice");
            }
            vofs = argv[i];
            break;
        case T_ARRAY:
            if (vaxes) {
                rb_raise(rb_eArgError,"axes-array is given twice");
            }
            vaxes = argv[i];
            break;
        }
    }

    if (vofs) {
        kofs = NUM2SSIZET(vofs);
    } else {
        kofs = 0;
    }

    GetNArray(self,na);
    nd = na->ndim;
    if (nd < 2) {
        rb_raise(nary_eDimensionError,"less than 2-d array");
    }

    if (vaxes) {
        if (RARRAY_LEN(vaxes) != 2) {
            rb_raise(rb_eArgError,"axes must be 2-element array");
        }
        ax[0] = NUM2INT(RARRAY_AREF(vaxes,0));
        ax[1] = NUM2INT(RARRAY_AREF(vaxes,1));
        if (ax[0]<-nd || ax[0]>=nd || ax[1]<-nd || ax[1]>=nd) {
            rb_raise(rb_eArgError,"axis out of range:[%d,%d]",ax[0],ax[1]);
        }
        if (ax[0]<0) {ax[0] += nd;}
        if (ax[1]<0) {ax[1] += nd;}
        if (ax[0]==ax[1]) {
            rb_raise(rb_eArgError,"same axes:[%d,%d]",ax[0],ax[1]);
        }
    } else {
        ax[0] = nd-2;
        ax[1] = nd-1;
    }

    // Diagonal offset from the main diagonal.
    if (kofs >= 0) {
        k0 = 0;
        k1 = kofs;
        if (k1 >= na->shape[ax[1]]) {
            rb_raise(rb_eArgError,"invalid diagonal offset(%"SZF"d) for "
                     "last dimension size(%"SZF"d)",kofs,na->shape[ax[1]]);
        }
    } else {
        k0 = -kofs;
        k1 = 0;
        if (k0 >= na->shape[ax[0]]) {
            rb_raise(rb_eArgError,"invalid diagonal offset(=%"SZF"d) for "
                     "last-1 dimension size(%"SZF"d)",kofs,na->shape[ax[0]]);
        }
    }

    diag_size = MIN(na->shape[ax[0]]-k0,na->shape[ax[1]]-k1);

    // new shape
    shape = ALLOCA_N(size_t,nd-1);
    for (i=k=0; i<nd; i++) {
        if (i != ax[0] && i != ax[1]) {
            shape[k++] = na->shape[i];
        }
    }
    shape[k] = diag_size;

    // new object
    view = na_s_allocate_view(CLASS_OF(self));
    na_copy_flags(self, view);
    GetNArrayView(view, na2);

    // new stride
    na_setup_shape((narray_t*)na2, nd-1, shape);
    na2->stridx = ALLOC_N(stridx_t, nd-1);

    switch(na->type) {
    case NARRAY_DATA_T:
    case NARRAY_FILEMAP_T:
        na2->offset = 0;
        na2->data = self;
        stride = stride0 = stride1 = nary_element_stride(self);
        for (i=nd,k=nd-2; i--; ) {
            if (i==ax[1]) {
                stride1 = stride;
                if (kofs > 0) {
                    na2->offset = kofs*stride;
                }
            } else if (i==ax[0]) {
                stride0 = stride;
                if (kofs < 0) {
                    na2->offset = (-kofs)*stride;
                }
            } else {
                SDX_SET_STRIDE(na2->stridx[--k],stride);
            }
            stride *= na->shape[i];
        }
        SDX_SET_STRIDE(na2->stridx[nd-2],stride0+stride1);
        break;

    case NARRAY_VIEW_T:
        GetNArrayView(self, na1);
        na2->data = na1->data;
        na2->offset = na1->offset;
        for (i=k=0; i<nd; i++) {
            if (i != ax[0] && i != ax[1]) {
                if (SDX_IS_INDEX(na1->stridx[i])) {
                    idx0 = SDX_GET_INDEX(na1->stridx[i]);
                    idx1 = ALLOC_N(size_t, na->shape[i]);
                    for (j=0; j<na->shape[i]; j++) {
                        idx1[j] = idx0[j];
                    }
                    SDX_SET_INDEX(na2->stridx[k],idx1);
                } else {
                    na2->stridx[k] = na1->stridx[i];
                }
                k++;
            }
        }
        if (SDX_IS_INDEX(na1->stridx[ax[0]])) {
            idx0 = SDX_GET_INDEX(na1->stridx[ax[0]]);
            diag_idx = ALLOC_N(size_t, diag_size);
            if (SDX_IS_INDEX(na1->stridx[ax[1]])) {
                idx1 = SDX_GET_INDEX(na1->stridx[ax[1]]);
                for (j=0; j<diag_size; j++) {
                    diag_idx[j] = idx0[j+k0] + idx1[j+k1];
                }
            } else {
                stride1 = SDX_GET_STRIDE(na1->stridx[ax[1]]);
                for (j=0; j<diag_size; j++) {
                    diag_idx[j] = idx0[j+k0] + stride1*(j+k1);
                }
            }
            SDX_SET_INDEX(na2->stridx[nd-2],diag_idx);
        } else {
            stride0 = SDX_GET_STRIDE(na1->stridx[ax[0]]);
            if (SDX_IS_INDEX(na1->stridx[ax[1]])) {
                idx1 = SDX_GET_INDEX(na1->stridx[ax[1]]);
                diag_idx = ALLOC_N(size_t, diag_size);
                for (j=0; j<diag_size; j++) {
                    diag_idx[j] = stride0*(j+k0) + idx1[j+k1];
                }
                SDX_SET_INDEX(na2->stridx[nd-2],diag_idx);
            } else {
                stride1 = SDX_GET_STRIDE(na1->stridx[ax[1]]);
                na2->offset += stride0*k0 + stride1*k1;
                SDX_SET_STRIDE(na2->stridx[nd-2],stride0+stride1);
            }
        }
        break;
    }
    return view;
}

#diff(n = 1, axis: -1)) ⇒ Object

Calculate the n-th discrete difference along given axis.

Examples:

p x = Numo::DFloat[1, 2, 4, 7, 0]
# Numo::DFloat#shape=[5]
# [1, 2, 4, 7, 0]

p x.diff
# Numo::DFloat#shape=[4]
# [1, 2, 3, -7]

p x.diff(2)
# Numo::DFloat#shape=[3]
# [1, 1, -10]

p x = Numo::DFloat[[1, 3, 6, 10], [0, 5, 6, 8]]
# Numo::DFloat#shape=[2,4]
# [[1, 3, 6, 10],
#  [0, 5, 6, 8]]

p x.diff
# Numo::DFloat#shape=[2,3]
# [[2, 3, 4],
#  [5, 1, 2]]

p x.diff(axis:0)
# Numo::DFloat#shape=[1,4]
# [[-1, 2, 0, -2]]


934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
# File 'lib/numo/narray/extra.rb', line 934

def diff(n=1,axis:-1)
  axis = check_axis(axis)
  if n < 0 || n >= shape[axis]
    raise ShapeError,"n=#{n} is invalid for shape[#{axis}]=#{shape[axis]}"
  end
  # calculate polynomial coefficient
  c = self.class[-1,1]
  2.upto(n) do |i|
    x = self.class.zeros(i+1)
    x[0..-2] = c
    y = self.class.zeros(i+1)
    y[1..-1] = c
    c = y - x
  end
  s = [true]*ndim
  s[axis] = n..-1
  result = self[*s].dup
  sum = result.inplace
  (n-1).downto(0) do |i|
    s = [true]*ndim
    s[axis] = i..-n-1+i
    sum + self[*s] * c[i] # inplace addition
  end
  return result
end

#dot(b) ⇒ Numo::NArray

Dot product of two arrays.

Parameters:

Returns:



1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
# File 'lib/numo/narray/extra.rb', line 1085

def dot(b)
  t = self.class::UPCAST[b.class]
  if defined?(Linalg) && [SFloat,DFloat,SComplex,DComplex].include?(t)
    Linalg.dot(self,b)
  else
    b = self.class.asarray(b)
    case b.ndim
    when 1
      mulsum(b, axis:-1)
    else
      case ndim
      when 0
        b.mulsum(self, axis:-2)
      when 1
        self[true,:new].mulsum(b, axis:-2)
      else
        unless @@warn_slow_dot
          nx = 200
          ns = 200000
          am,an = shape[-2..-1]
          bm,bn = b.shape[-2..-1]
          if am > nx && an > nx && bm > nx && bn > nx &&
              size > ns && b.size > ns
            @@warn_slow_dot = true
            warn "\nwarning: Built-in matrix dot is slow. Consider installing Numo::Linalg.\n\n"
          end
        end
        self[false,:new].mulsum(b[false,:new,true,true], axis:-2)
      end
    end
  end
end

#dsplit(indices_or_sections) ⇒ Object



760
761
762
# File 'lib/numo/narray/extra.rb', line 760

def dsplit(indices_or_sections)
  split(indices_or_sections, axis:2)
end

#empty?Boolean

Returns true if self.size == 0.

Returns:

  • (Boolean)


724
725
726
727
728
729
730
731
732
733
# File 'ext/numo/narray/narray.c', line 724

static VALUE
na_empty_p(VALUE self)
{
    narray_t *na;
    GetNArray(self,na);
    if (NA_SIZE(na)==0) {
        return Qtrue;
    }
    return Qfalse;
}

#expand_dims(dim) ⇒ Numo::NArray

Expand the shape of an array. Insert a new axis with size=1 at a given dimension.

Parameters:

  • dim (Integer)

    dimension at which new axis is inserted.

Returns:



973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
# File 'ext/numo/narray/narray.c', line 973

VALUE
na_expand_dims(VALUE self, VALUE vdim)
{
    int  i, j, nd, dim;
    size_t *shape, *na_shape;
    stridx_t *stridx, *na_stridx;
    narray_t *na;
    narray_view_t *na2;
    VALUE view;

    GetNArray(self,na);
    nd = na->ndim;

    dim = NUM2INT(vdim);
    if (dim < -nd-1 || dim > nd) {
        rb_raise(nary_eDimensionError,"invalid axis (%d for %dD NArray)",
                 dim,nd);
    }
    if (dim < 0) {
        dim += nd+1;
    }

    view = na_make_view(self);
    GetNArrayView(view, na2);

    shape = ALLOC_N(size_t,nd+1);
    stridx = ALLOC_N(stridx_t,nd+1);
    na_shape = na2->base.shape;
    na_stridx = na2->stridx;

    for (i=j=0; i<=nd; i++) {
        if (i==dim) {
            shape[i] = 1;
            SDX_SET_STRIDE(stridx[i],0);
        } else {
            shape[i] = na_shape[j];
            stridx[i] = na_stridx[j];
            j++;
        }
    }

    na2->stridx = stridx;
    xfree(na_stridx);
    na2->base.shape = shape;
    if (na_shape != &(na2->base.size)) {
        xfree(na_shape);
    }
    na2->base.ndim++;
    return view;
}

#flattenObject

deprecated



549
550
551
552
553
# File 'ext/numo/narray/data.c', line 549

VALUE
na_flatten(VALUE self)
{
    return na_flatten_dim(self,0);
}

#fliplrObject

Flip each row in the left/right direction. Same as a[true, (-1..0).step(-1), ...].



36
37
38
# File 'lib/numo/narray/extra.rb', line 36

def fliplr
  reverse(1)
end

#flipudObject

Flip each column in the up/down direction. Same as a[(-1..0).step(-1), ...].



42
43
44
# File 'lib/numo/narray/extra.rb', line 42

def flipud
  reverse(0)
end

#host_order?Boolean Also known as: little_endian?, vacs_order?

Return true if not byte swapped.

Returns:

  • (Boolean)


1650
1651
1652
1653
1654
1655
# File 'ext/numo/narray/narray.c', line 1650

VALUE na_host_order_p( VALUE self )
{
    if (TEST_BYTE_SWAPPED(self))
      return Qfalse;
    return Qtrue;
}

#hsplit(indices_or_sections) ⇒ Object



756
757
758
# File 'lib/numo/narray/extra.rb', line 756

def hsplit(indices_or_sections)
  split(indices_or_sections, axis:1)
end

#initialize_copy(other) ⇒ Numo::NArray

Replaces the contents of self with the contents of other narray. Used in dup and clone method.

Parameters:

Returns:



423
424
425
426
427
428
429
430
431
432
433
# File 'ext/numo/narray/narray.c', line 423

static VALUE
na_initialize_copy(VALUE self, VALUE orig)
{
    narray_t *na;
    GetNArray(orig,na);

    na_setup(self,NA_NDIM(na),NA_SHAPE(na));
    na_store(self,orig);
    na_copy_flags(orig,self);
    return self;
}

#inner(b, axis: -1)) ⇒ Numo::NArray

Inner product of two arrays. Same as (a*b).sum(axis:-1).

Parameters:

Returns:



1124
1125
1126
# File 'lib/numo/narray/extra.rb', line 1124

def inner(b, axis:-1)
  mulsum(b, axis:axis)
end

#inplaceNumo::NArray

Returns view of narray with inplace flagged.

Returns:



1662
1663
1664
1665
1666
1667
1668
# File 'ext/numo/narray/narray.c', line 1662

VALUE na_inplace( VALUE self )
{
    VALUE view = self;
    view = na_make_view(self);
    SET_INPLACE(view);
    return view;
}

#inplace!Numo::NArray

Set inplace flag to self.

Returns:



1674
1675
1676
1677
1678
# File 'ext/numo/narray/narray.c', line 1674

VALUE na_inplace_bang( VALUE self )
{
    SET_INPLACE(self);
    return self;
}

#inplace?Boolean

Return true if inplace flagged.

Returns:

  • (Boolean)


1691
1692
1693
1694
1695
1696
1697
# File 'ext/numo/narray/narray.c', line 1691

VALUE na_inplace_p( VALUE self )
{
    if (TEST_INPLACE(self))
        return Qtrue;
    else
        return Qfalse;
}

#insert(indice, values, axis: nil) ⇒ Object

Insert values along the axis before the indices.

Examples:

p a = Numo::DFloat[[1, 2], [3, 4]]
a = Numo::Int32[[1, 1], [2, 2], [3, 3]]

p a.insert(1,5)
# Numo::Int32#shape=[7]
# [1, 5, 1, 2, 2, 3, 3]

p a.insert(1, 5, axis:1)
# Numo::Int32#shape=[3,3]
# [[1, 5, 1],
#  [2, 5, 2],
#  [3, 5, 3]]

p a.insert([1], [[11],[12],[13]], axis:1)
# Numo::Int32#shape=[3,3]
# [[1, 11, 1],
#  [2, 12, 2],
#  [3, 13, 3]]

p a.insert(1, [11, 12, 13], axis:1)
# Numo::Int32#shape=[3,3]
# [[1, 11, 1],
#  [2, 12, 2],
#  [3, 13, 3]]

p a.insert([1], [11, 12, 13], axis:1)
# Numo::Int32#shape=[3,5]
# [[1, 11, 12, 13, 1],
#  [2, 11, 12, 13, 2],
#  [3, 11, 12, 13, 3]]

p b = a.flatten
# Numo::Int32(view)#shape=[6]
# [1, 1, 2, 2, 3, 3]

p b.insert(2,[15,16])
# Numo::Int32#shape=[8]
# [1, 1, 15, 16, 2, 2, 3, 3]

p b.insert([2,2],[15,16])
# Numo::Int32#shape=[8]
# [1, 1, 15, 16, 2, 2, 3, 3]

p b.insert([2,1],[15,16])
# Numo::Int32#shape=[8]
# [1, 16, 1, 15, 2, 2, 3, 3]

p b.insert([2,0,1],[15,16,17])
# Numo::Int32#shape=[9]
# [16, 1, 17, 1, 15, 2, 2, 3, 3]

p b.insert(2..3, [15, 16])
# Numo::Int32#shape=[8]
# [1, 1, 15, 2, 16, 2, 3, 3]

p b.insert(2, [7.13, 0.5])
# Numo::Int32#shape=[8]
# [1, 1, 7, 0, 2, 2, 3, 3]

p x = Numo::DFloat.new(2,4).seq
# Numo::DFloat#shape=[2,4]
# [[0, 1, 2, 3],
#  [4, 5, 6, 7]]

p x.insert([1,3],999,axis:1)
# Numo::DFloat#shape=[2,6]
# [[0, 999, 1, 2, 999, 3],
#  [4, 999, 5, 6, 999, 7]]


349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
# File 'lib/numo/narray/extra.rb', line 349

def insert(indice,values,axis:nil)
  if axis
    values = self.class.asarray(values)
    nd = values.ndim
    midx = [:new]*(ndim-nd) + [true]*nd
    case indice
    when Numeric
      midx[-nd-1] = true
      midx[axis] = :new
    end
    values = values[*midx]
  else
    values = self.class.asarray(values).flatten
  end
  idx = Int64.asarray(indice)
  nidx = idx.size
  if nidx == 1
    nidx = values.shape[axis||0]
    idx = idx + Int64.new(nidx).seq
  else
    sidx = idx.sort_index
    idx[sidx] += Int64.new(nidx).seq
  end
  if axis
    bit = Bit.ones(shape[axis]+nidx)
    bit[idx] = 0
    new_shape = shape
    new_shape[axis] += nidx
    a = self.class.zeros(new_shape)
    mdidx = [true]*ndim
    mdidx[axis] = bit.where
    a[*mdidx] = self
    mdidx[axis] = idx
    a[*mdidx] = values
  else
    bit = Bit.ones(size+nidx)
    bit[idx] = 0
    a = self.class.zeros(size+nidx)
    a[bit.where] = self.flatten
    a[idx] = values
  end
  return a
end

#kron(b) ⇒ Numo::NArray

Kronecker product of two arrays.

kron(a,b)[k_0, k_1, ...] = a[i_0, i_1, ...] * b[j_0, j_1, ...]
   where:  k_n = i_n * b.shape[n] + j_n

Examples:

Numo::DFloat[1,10,100].kron([5,6,7])
=> Numo::DFloat#shape=[9]
[5, 6, 7, 50, 60, 70, 500, 600, 700]
Numo::DFloat[5,6,7].kron([1,10,100])
=> Numo::DFloat#shape=[9]
[5, 50, 500, 6, 60, 600, 7, 70, 700]
Numo::DFloat.eye(2).kron(Numo::DFloat.ones(2,2))
=> Numo::DFloat#shape=[4,4]
[[1, 1, 0, 0],
 [1, 1, 0, 0],
 [0, 0, 1, 1],
 [0, 0, 1, 1]]

Parameters:

Returns:



1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
# File 'lib/numo/narray/extra.rb', line 1188

def kron(b)
  b = NArray.cast(b)
  nda = ndim
  ndb = b.ndim
  shpa = shape
  shpb = b.shape
  adim = [:new]*(2*[ndb-nda,0].max) + [true,:new]*nda
  bdim = [:new]*(2*[nda-ndb,0].max) + [:new,true]*ndb
  shpr = (-[nda,ndb].max..-1).map{|i| (shpa[i]||1) * (shpb[i]||1)}
  (self[*adim] * b[*bdim]).reshape(*shpr)
end

#marshal_dumpArray

Dump marshal data.

Returns:

  • (Array)

    Array containing marshal data.



1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
# File 'ext/numo/narray/narray.c', line 1340

static VALUE
nary_marshal_dump(VALUE self)
{
    VALUE a;

    a = rb_ary_new();
    rb_ary_push(a, INT2FIX(1));     // version
    rb_ary_push(a, na_shape(self));
    rb_ary_push(a, INT2FIX(NA_FLAG0(self)));
    if (CLASS_OF(self) == numo_cRObject) {
        narray_t *na;
        VALUE *ptr;
        size_t offset=0;
        GetNArray(self,na);
        if (na->type == NARRAY_VIEW_T) {
            if (na_check_contiguous(self)==Qtrue) {
                offset = NA_VIEW_OFFSET(na);
            } else {
                self = rb_funcall(self,id_dup,0);
            }
        }
        ptr = (VALUE*)na_get_pointer_for_read(self);
        rb_ary_push(a, rb_ary_new4(NA_SIZE(na), ptr+offset));
    } else {
        rb_ary_push(a, nary_to_binary(self));
    }
    RB_GC_GUARD(self);
    return a;
}

#marshal_load(data) ⇒ nil

Load marshal data.

Returns:

  • (nil)


1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
# File 'ext/numo/narray/narray.c', line 1377

static VALUE
nary_marshal_load(VALUE self, VALUE a)
{
    VALUE v;

    if (TYPE(a) != T_ARRAY) {
        rb_raise(rb_eArgError,"marshal argument should be array");
    }
    if (RARRAY_LEN(a) != 4) {
        rb_raise(rb_eArgError,"marshal array size should be 4");
    }
    if (RARRAY_AREF(a,0) != INT2FIX(1)) {
        rb_raise(rb_eArgError,"NArray marshal version %d is not supported "
                 "(only version 1)", NUM2INT(RARRAY_AREF(a,0)));
    }
    na_initialize(self,RARRAY_AREF(a,1));
    NA_FL0_SET(self,FIX2INT(RARRAY_AREF(a,2)));
    v = RARRAY_AREF(a,3);
    if (CLASS_OF(self) == numo_cRObject) {
        narray_t *na;
        char *ptr;
        if (TYPE(v) != T_ARRAY) {
            rb_raise(rb_eArgError,"RObject content should be array");
        }
        GetNArray(self,na);
        if (RARRAY_LEN(v) != (long)NA_SIZE(na)) {
            rb_raise(rb_eArgError,"RObject content size mismatch");
        }
        ptr = na_get_pointer_for_write(self);
        memcpy(ptr, RARRAY_PTR(v), NA_SIZE(na)*sizeof(VALUE));
    } else {
        nary_store_binary(1,&v,self);
        if (TEST_BYTE_SWAPPED(self)) {
            rb_funcall(na_inplace(self),id_to_host,0);
            REVERSE_ENDIAN(self); // correct behavior??
        }
    }
    RB_GC_GUARD(a);
    return self;
}

#ndimObject Also known as: rank

method: size() – returns the total number of typeents



711
712
713
714
715
716
717
# File 'ext/numo/narray/narray.c', line 711

static VALUE
na_ndim(VALUE self)
{
    narray_t *na;
    GetNArray(self,na);
    return INT2NUM(na->ndim);
}

#new_fill(value) ⇒ Object

Return an array filled with value with the same shape and type as self.



20
21
22
# File 'lib/numo/narray/extra.rb', line 20

def new_fill(value)
  self.class.new(*shape).fill(value)
end

#new_narrayObject

Return an unallocated array with the same shape and type as self.



5
6
7
# File 'lib/numo/narray/extra.rb', line 5

def new_narray
  self.class.new(*shape)
end

#new_onesObject

Return an array of ones with the same shape and type as self.



15
16
17
# File 'lib/numo/narray/extra.rb', line 15

def new_ones
  self.class.ones(*shape)
end

#new_zerosObject

Return an array of zeros with the same shape and type as self.



10
11
12
# File 'lib/numo/narray/extra.rb', line 10

def new_zeros
  self.class.zeros(*shape)
end

#out_of_place!Numo::NArray Also known as: not_inplace!

Unset inplace flag to self.

Returns:



1703
1704
1705
1706
1707
# File 'ext/numo/narray/narray.c', line 1703

VALUE na_out_of_place_bang( VALUE self )
{
    UNSET_INPLACE(self);
    return self;
}

#outer(b, axis: nil) ⇒ Numo::NArray

Outer product of two arrays. Same as self[false,:new] * b[false,:new,true].

Examples:

a = Numo::DFloat.ones(5)
=> Numo::DFloat#shape=[5]
[1, 1, 1, 1, 1]
b = Numo::DFloat.linspace(-2,2,5)
=> Numo::DFloat#shape=[5]
[-2, -1, 0, 1, 2]
a.outer(b)
=> Numo::DFloat#shape=[5,5]
[[-2, -1, 0, 1, 2],
 [-2, -1, 0, 1, 2],
 [-2, -1, 0, 1, 2],
 [-2, -1, 0, 1, 2],
 [-2, -1, 0, 1, 2]]

Parameters:

  • b (Numo::NArray)
  • axis (Integer)

    applied axis (default=-1)

Returns:



1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
# File 'lib/numo/narray/extra.rb', line 1149

def outer(b, axis:nil)
  b = NArray.cast(b)
  if axis.nil?
    self[false,:new] * ((b.ndim==0) ? b : b[false,:new,true])
  else
    md,nd = [ndim,b.ndim].minmax
    axis = check_axis(axis) - nd
    if axis < -md
      raise ArgumentError,"axis=#{axis} is out of range"
    end
    adim = [true]*ndim
    adim[axis+ndim+1,0] = :new
    bdim = [true]*b.ndim
    bdim[axis+b.ndim,0] = :new
    self[*adim] * b[*bdim]
  end
end

#rad2degObject

Convert angles from radians to degrees.



25
26
27
# File 'lib/numo/narray/extra.rb', line 25

def rad2deg
  self * (180/Math::PI)
end

#repeat(arg, axis: nil) ⇒ Object

Examples:

p Numo::NArray[3].repeat(4)
# Numo::Int32#shape=[4]
# [3, 3, 3, 3]

p x = Numo::NArray[[1,2],[3,4]]
# Numo::Int32#shape=[2,2]
# [[1, 2],
#  [3, 4]]

p x.repeat(2)
# Numo::Int32#shape=[8]
# [1, 1, 2, 2, 3, 3, 4, 4]

p x.repeat(3,axis:1)
# Numo::Int32#shape=[2,6]
# [[1, 1, 1, 2, 2, 2],
#  [3, 3, 3, 4, 4, 4]]

p x.repeat([1,2],axis:0)
# Numo::Int32#shape=[3,2]
# [[1, 2],
#  [3, 4],
#  [3, 4]]


872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
# File 'lib/numo/narray/extra.rb', line 872

def repeat(arg,axis:nil)
  case axis
  when Integer
    axis = check_axis(axis)
    c = self
  when NilClass
    c = self.flatten
    axis = 0
  else
    raise ArgumentError,"invalid axis"
  end
  case arg
  when Integer
    if !arg.kind_of?(Integer) || arg<1
      raise ArgumentError,"argument should be positive integer"
    end
    idx = c.shape[axis].times.map{|i| [i]*arg}.flatten
  else
    arg = arg.to_a
    if arg.size != c.shape[axis]
      raise ArgumentError,"repeat size shoud be equal to size along axis"
    end
    arg.each do |i|
      if !i.kind_of?(Integer) || i<0
        raise ArgumentError,"argument should be non-negative integer"
      end
    end
    idx = arg.each_with_index.map{|a,i| [i]*a}.flatten
  end
  ref = [true] * c.ndim
  ref[axis] = idx
  c[*ref].copy
end

#reshape(size0, size1, ...) ⇒ Numo::NArray

Copy and change the shape of NArray. Returns a copied NArray.

Parameters:

  • sizeN (Integer)

    new shape

Returns:



417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
# File 'ext/numo/narray/data.c', line 417

static VALUE
na_reshape(int argc, VALUE *argv, VALUE self)
{
    size_t *shape;
    narray_t *na;
    VALUE    copy;

    shape = ALLOCA_N(size_t, argc);
    na_check_reshape(argc, argv, self, shape);

    copy = rb_funcall(self, rb_intern("dup"), 0);
    GetNArray(copy, na);
    na_setup_shape(na, argc, shape);
    return copy;
}

#reshape!(size0, size1, ...) ⇒ Numo::NArray

Change the shape of self NArray without coping. Raise exception if self is non-contiguous.

Parameters:

  • sizeN (Integer)

    new shape

Returns:



391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
# File 'ext/numo/narray/data.c', line 391

static VALUE
na_reshape_bang(int argc, VALUE *argv, VALUE self)
{
    size_t *shape;
    narray_t *na;

    if (na_check_contiguous(self)==Qfalse) {
        rb_raise(rb_eStandardError, "cannot change shape of non-contiguous NArray");
    }
    shape = ALLOCA_N(size_t, argc);
    na_check_reshape(argc, argv, self, shape);

    GetNArray(self, na);
    na_setup_shape(na, argc, shape);
    return self;
}

#reverse([dim0,dim1,..]) ⇒ Object

Return reversed view along specified dimeinsion



1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
# File 'ext/numo/narray/narray.c', line 1032

VALUE
nary_reverse(int argc, VALUE *argv, VALUE self)
{
    int i, nd;
    size_t  j, n;
    size_t  offset;
    size_t *idx1, *idx2;
    ssize_t stride;
    ssize_t sign;
    narray_t *na;
    narray_view_t *na1, *na2;
    VALUE view;
    VALUE reduce;

    reduce = na_reduce_dimension(argc, argv, 1, &self, 0, 0);

    GetNArray(self,na);
    nd = na->ndim;

    view = na_s_allocate_view(CLASS_OF(self));

    na_copy_flags(self, view);
    GetNArrayView(view, na2);

    na_setup_shape((narray_t*)na2, nd, na->shape);
    na2->stridx = ALLOC_N(stridx_t,nd);

    switch(na->type) {
    case NARRAY_DATA_T:
    case NARRAY_FILEMAP_T:
        stride = nary_element_stride(self);
        offset = 0;
        for (i=nd; i--;) {
            if (na_test_reduce(reduce,i)) {
                offset += (na->shape[i]-1)*stride;
                sign = -1;
            } else {
                sign = 1;
            }
            SDX_SET_STRIDE(na2->stridx[i],stride*sign);
            stride *= na->shape[i];
        }
        na2->offset = offset;
        na2->data = self;
        break;
    case NARRAY_VIEW_T:
        GetNArrayView(self, na1);
        offset = na1->offset;
        for (i=0; i<nd; i++) {
            n = na1->base.shape[i];
            if (SDX_IS_INDEX(na1->stridx[i])) {
                idx1 = SDX_GET_INDEX(na1->stridx[i]);
                idx2 = ALLOC_N(size_t,n);
                if (na_test_reduce(reduce,i)) {
                    for (j=0; j<n; j++) {
                        idx2[n-1-j] = idx1[j];
                    }
                } else {
                    for (j=0; j<n; j++) {
                        idx2[j] = idx1[j];
                    }
                }
                SDX_SET_INDEX(na2->stridx[i],idx2);
            } else {
                stride = SDX_GET_STRIDE(na1->stridx[i]);
                if (na_test_reduce(reduce,i)) {
                    offset += (n-1)*stride;
                    SDX_SET_STRIDE(na2->stridx[i],-stride);
                } else {
                    na2->stridx[i] = na1->stridx[i];
                }
            }
        }
        na2->offset = offset;
        na2->data = na1->data;
        break;
    }

    return view;
}

#rot90(k = 1, axes = [0,1]) ⇒ Object

Rotate in the plane specified by axes.

Examples:

p a = Numo::Int32.new(2,2).seq
# Numo::Int32#shape=[2,2]
# [[0, 1],
#  [2, 3]]

p a.rot90
# Numo::Int32(view)#shape=[2,2]
# [[1, 3],
#  [0, 2]]

p a.rot90(2)
# Numo::Int32(view)#shape=[2,2]
# [[3, 2],
#  [1, 0]]

p a.rot90(3)
# Numo::Int32(view)#shape=[2,2]
# [[2, 0],
#  [3, 1]]


117
118
119
120
121
122
123
124
125
126
127
128
# File 'lib/numo/narray/extra.rb', line 117

def rot90(k=1,axes=[0,1])
  case k % 4
  when 0
    view
  when 1
    swapaxes(*axes).reverse(axes[0])
  when 2
    reverse(*axes)
  when 3
    swapaxes(*axes).reverse(axes[1])
  end
end

#row_major?Boolean

Return true if row major.

Returns:

  • (Boolean)


1628
1629
1630
1631
1632
1633
1634
# File 'ext/numo/narray/narray.c', line 1628

VALUE na_row_major_p( VALUE self )
{
    if (TEST_ROW_MAJOR(self))
	return Qtrue;
    else
	return Qfalse;
}

#shapeObject

method: shape() – returns shape, array of the size of dimensions



737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
# File 'ext/numo/narray/narray.c', line 737

static VALUE
 na_shape(VALUE self)
{
    volatile VALUE v;
    narray_t *na;
    size_t i, n, c, s;

    GetNArray(self,na);
    n = NA_NDIM(na);
    if (TEST_COLUMN_MAJOR(self)) {
        c = n-1;
        s = -1;
    } else {
        c = 0;
        s = 1;
    }
    v = rb_ary_new2(n);
    for (i=0; i<n; i++) {
        rb_ary_push(v, SIZET2NUM(na->shape[c]));
        c += s;
    }
    return v;
}

#sizeObject Also known as: length, total

method: size() – returns the total number of typeents



701
702
703
704
705
706
707
# File 'ext/numo/narray/narray.c', line 701

static VALUE
na_size(VALUE self)
{
    narray_t *na;
    GetNArray(self,na);
    return SIZET2NUM(na->size);
}

#split(indices_or_sections, axis: 0) ⇒ Object

Examples:

p x = Numo::DFloat.new(9).seq
# Numo::DFloat#shape=[9]
# [0, 1, 2, 3, 4, 5, 6, 7, 8]

pp x.split(3)
# [Numo::DFloat(view)#shape=[3]
# [0, 1, 2],
#  Numo::DFloat(view)#shape=[3]
# [3, 4, 5],
#  Numo::DFloat(view)#shape=[3]
# [6, 7, 8]]

p x = Numo::DFloat.new(8).seq
# Numo::DFloat#shape=[8]
# [0, 1, 2, 3, 4, 5, 6, 7]

pp x.split([3, 5, 6, 10])
# [Numo::DFloat(view)#shape=[3]
# [0, 1, 2],
#  Numo::DFloat(view)#shape=[2]
# [3, 4],
#  Numo::DFloat(view)#shape=[1]
# [5],
#  Numo::DFloat(view)#shape=[2]
# [6, 7],
#  Numo::DFloat(view)#shape=[0][]]


683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
# File 'lib/numo/narray/extra.rb', line 683

def split(indices_or_sections, axis:0)
  axis = check_axis(axis)
  size_axis = shape[axis]
  case indices_or_sections
  when Integer
    div_axis, mod_axis = size_axis.divmod(indices_or_sections)
    refs = [true]*ndim
    beg_idx = 0
    mod_axis.times.map do |i|
      end_idx = beg_idx + div_axis + 1
      refs[axis] = beg_idx ... end_idx
      beg_idx = end_idx
      self[*refs]
    end +
    (indices_or_sections-mod_axis).times.map do |i|
      end_idx = beg_idx + div_axis
      refs[axis] = beg_idx ... end_idx
      beg_idx = end_idx
      self[*refs]
    end
  when NArray
    split(indices_or_sections.to_a,axis:axis)
  when Array
    refs = [true]*ndim
    fst = 0
    (indices_or_sections + [size_axis]).map do |lst|
      lst = size_axis if lst > size_axis
      refs[axis] = (fst < size_axis) ? fst...lst : -1...-1
      fst = lst
      self[*refs]
    end
  else
    raise TypeError,"argument must be Integer or Array"
  end
end

#store_binary(string, [offset]) ⇒ Integer

Returns a new 1-D array initialized from binary raw data in a string.

Parameters:

  • string (String)

    Binary raw data.

  • (optional) (Integer)

    offset Byte offset in string.

Returns:

  • (Integer)

    stored length.



1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
# File 'ext/numo/narray/narray.c', line 1267

static VALUE
nary_store_binary(int argc, VALUE *argv, VALUE self)
{
    size_t size, str_len, byte_size, offset;
    char *ptr;
    int   narg;
    VALUE vstr, voffset;
    VALUE velmsz;
    narray_t *na;

    narg = rb_scan_args(argc,argv,"11",&vstr,&voffset);
    str_len = RSTRING_LEN(vstr);
    if (narg==2) {
        offset = NUM2SIZET(voffset);
        if (str_len < offset) {
            rb_raise(rb_eArgError, "offset is larger than string length");
        }
        str_len -= offset;
    } else {
        offset = 0;
    }

    GetNArray(self,na);
    size = NA_SIZE(na);
    velmsz = rb_const_get(CLASS_OF(self), id_element_byte_size);
    if (FIXNUM_P(velmsz)) {
        byte_size = size * NUM2SIZET(velmsz);
    } else {
        byte_size = ceil(size * NUM2DBL(velmsz));
    }
    if (byte_size > str_len) {
        rb_raise(rb_eArgError, "string is too short to store");
    }

    ptr = na_get_pointer_for_write(self);
    memcpy(ptr, RSTRING_PTR(vstr)+offset, byte_size);

    return SIZET2NUM(byte_size);
}

#swap_byteObject Also known as: hton



110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
# File 'ext/numo/narray/data.c', line 110

static VALUE
nary_swap_byte(VALUE self)
{
    VALUE v;
    ndfunc_arg_in_t ain[1] = {{Qnil,0}};
    ndfunc_arg_out_t aout[1] = {{INT2FIX(0),0}};
    ndfunc_t ndf = { iter_swap_byte, FULL_LOOP|NDF_ACCEPT_BYTESWAP,
                     1, 1, ain, aout };

    v = na_ndloop(&ndf, 1, self);
    if (self!=v) {
        na_copy_flags(self, v);
    }
    REVERSE_ENDIAN(v);
    return v;
}

#swapaxes(axis1, axis2) ⇒ Numo::NArray

Interchange two axes.

Examples:

x = Numo::Int32[[1,2,3]]

p x.swapaxes(0,1)
# Numo::Int32(view)#shape=[3,1]
# [[1],
#  [2],
#  [3]]

p x = Numo::Int32[[[0,1],[2,3]],[[4,5],[6,7]]]
# Numo::Int32#shape=[2,2,2]
# [[[0, 1],
#   [2, 3]],
#  [[4, 5],
#   [6, 7]]]

p x.swapaxes(0,2)
# Numo::Int32(view)#shape=[2,2,2]
# [[[0, 4],
#   [2, 6]],
#  [[1, 5],
#   [3, 7]]]

Parameters:

  • axis1 (Integer)
  • axis2 (Integer)

Returns:



209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
# File 'ext/numo/narray/data.c', line 209

VALUE
na_swapaxes(VALUE self, VALUE a1, VALUE a2)
{
    int  i, j, ndim;
    size_t tmp_shape;
    stridx_t tmp_stridx;
    narray_view_t *na;
    volatile VALUE view;

    view = na_make_view(self);
    GetNArrayView(view,na);

    ndim = na->base.ndim;
    i = check_axis(NUM2INT(a1), ndim);
    j = check_axis(NUM2INT(a2), ndim);

    tmp_shape = na->base.shape[i];
    tmp_stridx = na->stridx[i];
    na->base.shape[i] = na->base.shape[j];
    na->stridx[i] = na->stridx[j];
    na->base.shape[j] = tmp_shape;
    na->stridx[j] = tmp_stridx;

    return view;
}

#tile(*arg) ⇒ Object

Examples:

p a = Numo::NArray[0,1,2]
# Numo::Int32#shape=[3]
# [0, 1, 2]

p a.tile(2)
# Numo::Int32#shape=[6]
# [0, 1, 2, 0, 1, 2]

p a.tile(2,2)
# Numo::Int32#shape=[2,6]
# [[0, 1, 2, 0, 1, 2],
#  [0, 1, 2, 0, 1, 2]]

p a.tile(2,1,2)
# Numo::Int32#shape=[2,1,6]
# [[[0, 1, 2, 0, 1, 2]],
#  [[0, 1, 2, 0, 1, 2]]]

p b = Numo::NArray[[1, 2], [3, 4]]
# Numo::Int32#shape=[2,2]
# [[1, 2],
#  [3, 4]]

p b.tile(2)
# Numo::Int32#shape=[2,4]
# [[1, 2, 1, 2],
#  [3, 4, 3, 4]]

p b.tile(2,1)
# Numo::Int32#shape=[4,2]
# [[1, 2],
#  [3, 4],
#  [1, 2],
#  [3, 4]]

p c = Numo::NArray[1,2,3,4]
# Numo::Int32#shape=[4]
# [1, 2, 3, 4]

p c.tile(4,1)
# Numo::Int32#shape=[4,4]
# [[1, 2, 3, 4],
#  [1, 2, 3, 4],
#  [1, 2, 3, 4],
#  [1, 2, 3, 4]]


811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
# File 'lib/numo/narray/extra.rb', line 811

def tile(*arg)
  arg.each do |i|
    if !i.kind_of?(Integer) || i<1
      raise ArgumentError,"argument should be positive integer"
    end
  end
  ns = arg.size
  nd = self.ndim
  shp = self.shape
  new_shp = []
  src_shp = []
  res_shp = []
  (nd-ns).times do
    new_shp << 1
    new_shp << (n = shp.shift)
    src_shp << :new
    src_shp << true
    res_shp << n
  end
  (ns-nd).times do
    new_shp << (m = arg.shift)
    new_shp << 1
    src_shp << :new
    src_shp << :new
    res_shp << m
  end
  [nd,ns].min.times do
    new_shp << (m = arg.shift)
    new_shp << (n = shp.shift)
    src_shp << :new
    src_shp << true
    res_shp << n*m
  end
  self.class.new(*new_shp).store(self[*src_shp]).reshape(*res_shp)
end

#to_binaryString Also known as: to_string

Returns string containing the raw data bytes in NArray.

Returns:

  • (String)

    String object containing binary raw data.



1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
# File 'ext/numo/narray/narray.c', line 1312

static VALUE
nary_to_binary(VALUE self)
{
    size_t len, offset=0;
    char *ptr;
    VALUE str;
    narray_t *na;

    GetNArray(self,na);
    if (na->type == NARRAY_VIEW_T) {
        if (na_check_contiguous(self)==Qtrue) {
            offset = NA_VIEW_OFFSET(na);
        } else {
            self = rb_funcall(self,id_dup,0);
        }
    }
    len = NUM2SIZET(nary_byte_size(self));
    ptr = na_get_pointer_for_read(self);
    str = rb_usascii_str_new(ptr+offset,len);
    RB_GC_GUARD(self);
    return str;
}

#to_cObject



148
149
150
151
152
153
154
155
# File 'lib/numo/narray/extra.rb', line 148

def to_c
  if size==1
    Complex(self[0])
  else
    # convert to DComplex?
    raise TypeError, "can't convert #{self.class} into Complex"
  end
end

#to_fObject



139
140
141
142
143
144
145
146
# File 'lib/numo/narray/extra.rb', line 139

def to_f
  if size==1
    self[0].to_f
  else
    # convert to DFloat?
    raise TypeError, "can't convert #{self.class} into Float"
  end
end

#to_hostObject



146
147
148
149
150
151
152
153
# File 'ext/numo/narray/data.c', line 146

static VALUE
nary_to_host(VALUE self)
{
    if (TEST_HOST_ORDER(self)) {
        return self;
    }
    return rb_funcall(self, id_swap_byte, 0);
}

#to_iObject



130
131
132
133
134
135
136
137
# File 'lib/numo/narray/extra.rb', line 130

def to_i
  if size==1
    self[0].to_i
  else
    # convert to Int?
    raise TypeError, "can't convert #{self.class} into Integer"
  end
end

#to_networkObject



128
129
130
131
132
133
134
135
# File 'ext/numo/narray/data.c', line 128

static VALUE
nary_to_network(VALUE self)
{
    if (TEST_BIG_ENDIAN(self)) {
        return self;
    }
    return rb_funcall(self, id_swap_byte, 0);
}

#to_swappedObject



155
156
157
158
159
160
161
162
# File 'ext/numo/narray/data.c', line 155

static VALUE
nary_to_swapped(VALUE self)
{
    if (TEST_BYTE_SWAPPED(self)) {
        return self;
    }
    return rb_funcall(self, id_swap_byte, 0);
}

#to_vacsObject



137
138
139
140
141
142
143
144
# File 'ext/numo/narray/data.c', line 137

static VALUE
nary_to_vacs(VALUE self)
{
    if (TEST_LITTLE_ENDIAN(self)) {
        return self;
    }
    return rb_funcall(self, id_swap_byte, 0);
}

#trace(offset = nil, axis = nil, nan: false) ⇒ Object

Return the sum along diagonals of the array.

If 2-D array, computes the summation along its diagonal with the given offset, i.e., sum of a[i,i+offset]. If more than 2-D array, the diagonal is determined from the axes specified by axis argument. The default is axis=.

Parameters:

  • offset (Integer) (defaults to: nil)

    (optional, default=0) diagonal offset

  • axis (Array) (defaults to: nil)

    (optional, default=) diagonal axis

  • nan (Bool)

    (optional, default=false) nan-aware algorithm, i.e., if true then it ignores nan.



1074
1075
1076
# File 'lib/numo/narray/extra.rb', line 1074

def trace(offset=nil,axis=nil,nan:false)
  diagonal(offset,axis).sum(nan:nan,axis:-1)
end

#transpose(*args) ⇒ Object



265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
# File 'ext/numo/narray/data.c', line 265

VALUE
na_transpose(int argc, VALUE *argv, VALUE self)
{
    int ndim, *map, *permute;
    int i, d;
    bool is_positive, is_negative;
    narray_t *na1;

    GetNArray(self,na1);
    ndim = na1->ndim;
    if (ndim < 2) {
        if (argc > 0) {
            rb_raise(rb_eArgError, "unnecessary argument for 1-d array");
        }
        return na_make_view(self);
    }
    map = ALLOCA_N(int,ndim);
    if (argc == 0) {
        for (i=0; i < ndim; i++) {
            map[i] = ndim-1-i;
        }
        return na_transpose_map(self,map);
    }
    // with argument
    if (argc > ndim) {
        rb_raise(rb_eArgError, "more arguments than ndim");
    }
    for (i=0; i < ndim; i++) {
        map[i] = i;
    }
    permute = ALLOCA_N(int,argc);
    for (i=0; i < argc; i++) {
        permute[i] = 0;
    }
    is_positive = is_negative = 0;
    for (i=0; i < argc; i++) {
	if (TYPE(argv[i]) != T_FIXNUM) {
            rb_raise(rb_eArgError, "invalid argument");
        }
        d = FIX2INT(argv[i]);
        if (d >= 0) {
            if (d >= argc) {
                rb_raise(rb_eArgError, "out of dimension range");
            }
            if (is_negative) {
                rb_raise(rb_eArgError, "dimension must be non-negative only or negative only");
            }
            if (permute[d]) {
                rb_raise(rb_eArgError, "not permutation");
            }
            map[i] = d;
            permute[d] = 1;
            is_positive = 1;
        } else {
            if (d < -argc) {
                rb_raise(rb_eArgError, "out of dimension range");
            }
            if (is_positive) {
                rb_raise(rb_eArgError, "dimension must be non-negative only or negative only");
            }
            if (permute[argc+d]) {
                rb_raise(rb_eArgError, "not permutation");
            }
            map[ndim-argc+i] = ndim+d;
            permute[argc+d] = 1;
            is_negative = 1;
        }
    }
    return na_transpose_map(self,map);
}

#tril(k = 0) ⇒ Object

Lower triangular matrix. Return a copy with the elements above the k-th diagonal filled with zero.



1002
1003
1004
# File 'lib/numo/narray/extra.rb', line 1002

def tril(k=0)
  dup.tril!(k)
end

#tril!(k = 0) ⇒ Object

Lower triangular matrix. Fill the self elements above the k-th diagonal with zero.



1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
# File 'lib/numo/narray/extra.rb', line 1008

def tril!(k=0)
  if ndim < 2
    raise NArray::ShapeError, "must be >= 2-dimensional array"
  end
  if contiguous?
    idx = triu_indices(k+1)
    *shp,m,n = shape
    reshape!(*shp,m*n)
    self[false,idx] = 0
    reshape!(*shp,m,n)
  else
    store(tril(k))
  end
end

#tril_indices(k = 0) ⇒ Object

Return the indices for the lower-triangle on and below the k-th diagonal.



1024
1025
1026
1027
1028
1029
1030
# File 'lib/numo/narray/extra.rb', line 1024

def tril_indices(k=0)
  if ndim < 2
    raise NArray::ShapeError, "must be >= 2-dimensional array"
  end
  m,n = shape[-2..-1]
  NArray.tril_indices(m,n,k)
end

#triu(k = 0) ⇒ Object

Upper triangular matrix. Return a copy with the elements below the k-th diagonal filled with zero.



963
964
965
# File 'lib/numo/narray/extra.rb', line 963

def triu(k=0)
  dup.triu!(k)
end

#triu!(k = 0) ⇒ Object

Upper triangular matrix. Fill the self elements below the k-th diagonal with zero.



969
970
971
972
973
974
975
976
977
978
979
980
981
982
# File 'lib/numo/narray/extra.rb', line 969

def triu!(k=0)
  if ndim < 2
    raise NArray::ShapeError, "must be >= 2-dimensional array"
  end
  if contiguous?
    *shp,m,n = shape
    idx = tril_indices(k-1)
    reshape!(*shp,m*n)
    self[false,idx] = 0
    reshape!(*shp,m,n)
  else
    store(triu(k))
  end
end

#triu_indices(k = 0) ⇒ Object

Return the indices for the uppler-triangle on and above the k-th diagonal.



985
986
987
988
989
990
991
# File 'lib/numo/narray/extra.rb', line 985

def triu_indices(k=0)
  if ndim < 2
    raise NArray::ShapeError, "must be >= 2-dimensional array"
  end
  m,n = shape[-2..-1]
  NArray.triu_indices(m,n,k=0)
end

#viewObject

Return view of NArray



906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
# File 'ext/numo/narray/narray.c', line 906

VALUE
na_make_view(VALUE self)
{
    int i, nd;
    size_t  j;
    size_t *idx1, *idx2;
    ssize_t stride;
    narray_t *na;
    narray_view_t *na1, *na2;
    volatile VALUE view;

    GetNArray(self,na);
    nd = na->ndim;

    view = na_s_allocate_view(CLASS_OF(self));

    na_copy_flags(self, view);
    GetNArrayView(view, na2);

    na_setup_shape((narray_t*)na2, nd, na->shape);
    na2->stridx = ALLOC_N(stridx_t,nd);

    switch(na->type) {
    case NARRAY_DATA_T:
    case NARRAY_FILEMAP_T:
        stride = nary_element_stride(self);
        for (i=nd; i--;) {
            SDX_SET_STRIDE(na2->stridx[i],stride);
            stride *= na->shape[i];
        }
        na2->offset = 0;
        na2->data = self;
        break;
    case NARRAY_VIEW_T:
        GetNArrayView(self, na1);
        for (i=0; i<nd; i++) {
            if (SDX_IS_INDEX(na1->stridx[i])) {
                idx1 = SDX_GET_INDEX(na1->stridx[i]);
                idx2 = ALLOC_N(size_t,na1->base.shape[i]);
                for (j=0; j<na1->base.shape[i]; j++) {
                    idx2[j] = idx1[j];
                }
                SDX_SET_INDEX(na2->stridx[i],idx2);
            } else {
                na2->stridx[i] = na1->stridx[i];
            }
        }
        na2->offset = na1->offset;
        na2->data = na1->data;
        break;
    }

    return view;
}

#vsplit(indices_or_sections) ⇒ Object

Examples:

p x = Numo::DFloat.new(4,4).seq
# Numo::DFloat#shape=[4,4]
# [[0, 1, 2, 3],
#  [4, 5, 6, 7],
#  [8, 9, 10, 11],
#  [12, 13, 14, 15]]

pp x.hsplit(2)
# [Numo::DFloat(view)#shape=[4,2]
# [[0, 1],
#  [4, 5],
#  [8, 9],
#  [12, 13]],
#  Numo::DFloat(view)#shape=[4,2]
# [[2, 3],
#  [6, 7],
#  [10, 11],
#  [14, 15]]]

pp x.hsplit([3, 6])
# [Numo::DFloat(view)#shape=[4,3]
# [[0, 1, 2],
#  [4, 5, 6],
#  [8, 9, 10],
#  [12, 13, 14]],
#  Numo::DFloat(view)#shape=[4,1]
# [[3],
#  [7],
#  [11],
#  [15]],
#  Numo::DFloat(view)#shape=[4,0][]]


752
753
754
# File 'lib/numo/narray/extra.rb', line 752

def vsplit(indices_or_sections)
  split(indices_or_sections, axis:0)
end