Class: Cumo::NArray

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

Overview

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

Constant Summary collapse

@@warn_slow_dot = 
false

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.asarray(a) ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 155

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

.cast(a) ⇒ Object

Convert the argument to an narray if not an narray.



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# File 'lib/cumo/narray/extra.rb', line 139

def self.cast(a)
  case a
  when NArray
    a
  when Array,Numeric
    NArray.array_type(a).cast(a)
  else
    if a.respond_to?(:to_a)
      a = a.to_a
      NArray.array_type(a).cast(a)
    else
      raise TypeError,"invalid type for NArray"
    end
  end
end

.column_stack(arrays) ⇒ Object

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

Examples:

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


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# File 'lib/cumo/narray/extra.rb', line 644

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:

a = Cumo::DFloat[[1, 2], [3, 4]]
# => Cumo::DFloat#shape=[2,2]
# [[1, 2],
#  [3, 4]]

b = Cumo::DFloat[[5, 6]]
# => Cumo::DFloat#shape=[1,2]
# [[5, 6]]

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

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


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# File 'lib/cumo/narray/extra.rb', line 498

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 Cumo::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)
    if lst > fst
      refs[axis] = fst...lst
      result[*refs] = a
    end
  end
  result
end

.diag_indices(m, n, k = 0) ⇒ Object

Return the k-th diagonal indices.



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# File 'lib/cumo/narray/extra.rb', line 1138

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

.dstack(arrays) ⇒ Object

Stack arrays in depth wise (along third axis).

Examples:

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

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


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# File 'lib/cumo/narray/extra.rb', line 627

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

.hstack(arrays) ⇒ Object

Stack arrays horizontally (column wise).

Examples:

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

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


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# File 'lib/cumo/narray/extra.rb', line 597

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

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

parse matrix like matlab, octave

Examples:

a = Cumo::DFloat.parse %[
 2 -3 5
 4 9 7
 2 -1 6
]
# => Cumo::DFloat#shape=[3,3]
# [[2, -3, 5],
#  [4, 9, 7],
#  [2, -1, 6]]
a = Cumo::NArray.parse('true false nil')
# => Cumo::Bit#shape=[1,3]
# [[1, 0, 0]]


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# File 'lib/cumo/narray/extra.rb', line 182

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|
          item = item.strip
          c << parse_token(item) 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

.tril_indices(m, n, k = 0) ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 1122

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

.triu_indices(m, n, k = 0) ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 1083

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

.vstack(arrays) ⇒ Object

Stack arrays vertically (row wise).

Examples:

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

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


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# File 'lib/cumo/narray/extra.rb', line 574

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

Instance Method Details

#append(other, axis: nil) ⇒ Object

Append values to the end of an narray.

Examples:

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 312

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

#argsort(axis: -1) ⇒ Cumo::Int32

Returns an index array of sort result.

Examples:

require 'cumo/narray'

a = Cumo::DFloat[[0.1, 0.7],
                 [0.4, 0.2],
                 [0.2, 0.5]]
pp a.argsort
# =>
# Cumo::Int32#shape=[3,2]
# [[0, 1],
#  [1, 0],
#  [0, 1]]
pp a.argsort(axis: 0)
# =>
# Cumo::Int32#shape=[3,2]
# [[0, 1],
#  [2, 2],
#  [1, 0]]
pp a.argsort(axis: 1)
# =>
# Cumo::Int32#shape=[3,2]
# [[0, 1],
#  [1, 0],
#  [0, 1]]
pp a.argsort(axis: nil)
# =>
# Cumo::Int32#shape=[6]
# [0, 3, 4, 2, 5, 1]

Returns An array of indices that would sort the array.

Parameters:

  • axis (Integer, nil) (defaults to: -1) —

    Axis along which to sort. Default is -1 (the last axis). If nil is given, the array is flattened before sorting.

Returns:

  • (Cumo::Int32) —

    An array of indices that would sort the array.

Raises:

  • (NotImplementedError) 


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# File 'lib/cumo/narray/extra.rb', line 1188

def argsort(axis_ = 'none', axis: -1)
  raise NotImplementedError, "argsort is not implemented for #{self.class}" unless respond_to?(:sort_index)

  axis = axis_ unless axis_ == 'none'

  return flatten.sort_index if axis.nil?

  axis += ndim if axis < 0
  raise NArray::DimensionError, "dimension is out of range" if axis < 0 || axis >= ndim

  return sort_index if ndim == 1

  # sort_index answers with an index into the flattened array; the axes
  # after axis divide out of it and the ones before it fall to the modulo.
  idx = sort_index(axis)
  inner = shape[(axis + 1)..-1].reduce(1, :*)
  idx = idx / inner if inner > 1
  idx % shape[axis]
end

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

Examples:

a = Cumo::DFloat[[1, 2], [3, 4]]
# => Cumo::DFloat#shape=[2,2]
# [[1, 2],
#  [3, 4]]

b = Cumo::DFloat[[5, 6]]
# => Cumo::DFloat#shape=[1,2]
# [[5, 6]]

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

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


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# File 'lib/cumo/narray/extra.rb', line 699

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 Cumo::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
  if lst > 0
    refs[axis] = 0...lst
    result[*refs] = self
  end
  arrays.each do |a|
    fst = lst
    lst = fst + (a.shape[axis - ndim] || 1)
    if lst > fst
      refs[axis] = fst...lst
      result[*refs] = a
    end
  end
  result
end

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

Compute a covariance matrix.

Examples:

x = Cumo::DFloat[4, 5, 6]
x.cov
# => 1.0

x = Cumo::DFloat[[4, 5, 6], [3, 2, 1]]
x.cov
# => Cumo::DFloat#shape=[2,2]
# [[1, -1],
#  [-1, 1]]

y = Cumo::DFloat[7, 9, 8]
x.cov(y)
# => Cumo::DFloat#shape=[3,3]
# [[1, -1, 0.5],
#  [-1, 1, -0.5],
#  [0.5, -0.5, 1]]

Parameters:

  • y (Cumo::NArray) (defaults to: nil) —

    (optional) If not nil, the covariance matrix of self and y is computed.

  • ddof (Integer) (defaults to: 1) —

    (optional) Delta degrees of freedom. The divisor used in calculations is N - ddof, where N represents the number of observations.

  • fweights (Cumo::NArray) (defaults to: nil) —

    (optional) 1-D array of integer frequency weights.

  • aweights (Cumo::NArray) (defaults to: nil) —

    (optional) 1-D array of observation vector weights.

Returns:

Raises:

  • (NArray::ShapeError) 


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# File 'lib/cumo/narray/extra.rb', line 1433

def cov(y=nil, ddof:1, fweights:nil, aweights:nil)
  raise NArray::ShapeError, "ndim must be <= 2" if ndim > 2
  raise NArray::ShapeError, "y.ndim must be <= 2" if !y.nil? && y.ndim > 2
  raise ArgumentError, "ddof must be 0 or 1" unless [0, 1].include?(ddof)

  if y
    m = NArray.vstack([self, y])
  else
    m = self
  end
  w = nil
  if fweights
    fweights = NArray.cast(fweights) unless fweights.is_a?(NArray)
    raise ArgumentError, "fweights must be 1-D array" unless fweights.ndim == 1
    raise ArgumentError, "fweights size is wrong" unless fweights.size == m.shape[1]
    raise ArgumentError, "fweights must be non-negative" if (fweights < 0).any?
    raise ArgumentError, "fweights must be integer" unless fweights == fweights.floor
    w = fweights
  end
  if aweights
    aweights = NArray.cast(aweights) unless aweights.is_a?(NArray)
    raise ArgumentError, "aweights must be 1-D array" unless aweights.ndim == 1
    raise ArgumentError, "aweights size is wrong" unless aweights.size == m.shape[1]
    raise ArgumentError, "aweights must be non-negative" if (aweights < 0).any?
    if w.nil?
      w = aweights
    else
      w *= aweights
    end
  end
  if w.nil?
    fact = m.shape[-1] - ddof
  elsif ddof == 0
    fact = w.sum
  elsif aweights.nil?
    fact = w.sum - ddof
  else
    w_sum = w.sum
    fact = w_sum - ddof * (w * aweights).sum / w_sum
  end
  # numo's sum answers with a Ruby number, cumo's with a zero-dimensional
  # array, and every object is truthy.
  fact = fact.extract_cpu if fact.is_a?(NArray)
  if fact <= 0
    warn("Degrees of freedom <= 0 for slice")
    fact = 0.0
  end
  if w.nil?
    m -= m.mean(axis:-1, keepdims:true)
    mw = m
  else
    m -= (m * w).sum(axis:-1, keepdims:true) / w.sum
    mw = m * w
  end
  m.dot(mw.transpose.conj) / fact
end

#deg2rad ⇒ Object

Convert angles from degrees to radians.



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# File 'lib/cumo/narray/extra.rb', line 61

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

#delete(indice, axis = nil) ⇒ Object

Examples:

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 347

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.



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# File 'lib/cumo/narray/extra.rb', line 1145

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.



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# File 'lib/cumo/narray/extra.rb', line 1129

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

#diff(n = 1, axis: -1)) ⇒ Object

Calculate the n-th discrete difference along given axis.

Examples:

x = Cumo::DFloat[1, 2, 4, 7, 0]
# => Cumo::DFloat#shape=[5]
# [1, 2, 4, 7, 0]

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

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

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 1023

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) ⇒ Cumo::NArray

Dot product of two arrays.

Parameters:

Returns:



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# File 'lib/cumo/narray/extra.rb', line 1234

def dot(b)
  t = self.class::UPCAST[b.class]
  # Cumo::Bit names every other type but no table names Bit, so a pair can be
  # declared on one side only. cumo_na_upcast reads both tables; do the same
  # here, or the pair silently takes the slow route.
  t ||= b.class::UPCAST[self.class] if b.is_a?(NArray)
  if self.ndim == 0 and b.ndim == 0
    return self * b
  end
  if GEMM_TYPES.include?(t)
    a = t.cast(self)
    b = t.asarray(t.cast(b))
    case a.ndim
    when 1
      case b.ndim
      when 1
        a.mulsum(b, axis:-1)
      else
        a[:new, false].gemm(b).flatten
      end
    else
      case b.ndim
      when 1
        a.gemm(b[false, :new]).flatten
      else
        a.gemm(b)
      end
    end
  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: matrix dot for #{t} is slow. Consider SFloat, DFloat, SComplex, or DComplex to use cuBLAS, or BFloat or HFloat where sixteen bits are enough.\n\n"
          end
        end
        self[false, :new].mulsum(b[false, :new, true, true], axis:-2)
      end
    end
  end
end

#dsplit(indices_or_sections) ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 849

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

#each_over_axis(axis = 0) ⇒ Object

Iterate over an axis

Examples:

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

> a.each_over_axis{|i| p i}
Cumo::DFloat(view)#shape=[2,2]
[[0, 1],
 [2, 3]]
Cumo::DFloat(view)#shape=[2,2]
[[4, 5],
 [6, 7]]

> a.each_over_axis(1){|i| p i}
Cumo::DFloat(view)#shape=[2,2]
[[0, 1],
 [4, 5]]
Cumo::DFloat(view)#shape=[2,2]
[[2, 3],
 [6, 7]]


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# File 'lib/cumo/narray/extra.rb', line 272

def each_over_axis(axis=0)
  unless block_given?
    return to_enum(:each_over_axis, axis)
  end
  if ndim == 0
    if axis != 0
      raise ArgumentError, "axis=#{axis} is invalid"
    end
    niter = 1
  else
    axis = check_axis(axis)
    niter = shape[axis]
  end
  idx = [true] * ndim
  niter.times do |i|
    idx[axis] = i
    yield(self[*idx])
  end
  self
end

#fliplr ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 67

def fliplr
  reverse(1)
end

#flipud ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 73

def flipud
  reverse(0)
end

#get(out = nil, stream: nil) ⇒ Object

Copies this array to the host. Into a Cumo::CUDA::PinnedMemory it is asynchronous on the current stream, or on stream:, and answers the buffer; with nothing to copy into it answers the bytes as a String.



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# File 'lib/cumo/narray/extra.rb', line 24

def get(out = nil, stream: nil)
  case out
  when nil
    raise ArgumentError, "a String is copied synchronously, so it takes no stream:" unless stream.nil?
    to_binary
  when Cumo::CUDA::PinnedMemory
    out.copy(self, :to_pinned, stream)
  else
    raise TypeError, "get takes a Cumo::CUDA::PinnedMemory or nothing, got a #{out.class}"
  end
end

#hsplit(indices_or_sections) ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 845

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

#inner(b, axis: -1)) ⇒ Cumo::NArray

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

Parameters:

  • b (Cumo::NArray)
  • axis (Integer) (defaults to: -1)) —

    applied axis

Returns:



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# File 'lib/cumo/narray/extra.rb', line 1297

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

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

Insert values along the axis before the indices.

Examples:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 432

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) ⇒ Cumo::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:

Cumo::DFloat[1,10,100].kron([5,6,7])
# => Cumo::DFloat#shape=[9]
# [5, 6, 7, 50, 60, 70, 500, 600, 700]

Cumo::DFloat[5,6,7].kron([1,10,100])
# => Cumo::DFloat#shape=[9]
# [5, 50, 500, 6, 60, 600, 7, 70, 700]

Cumo::DFloat.eye(2).kron(Cumo::DFloat.ones(2,2))
# => Cumo::DFloat#shape=[4,4]
# [[1, 1, 0, 0],
#  [1, 1, 0, 0],
#  [0, 0, 1, 1],
#  [0, 0, 1, 1]]

Parameters:

Returns:



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# File 'lib/cumo/narray/extra.rb', line 1394

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

#new_fill(value) ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 51

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

#new_narray ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 36

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

#new_ones ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 46

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

#new_zeros ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 41

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

#outer(b, axis: nil) ⇒ Cumo::NArray

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

Examples:

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

b = Cumo::DFloat.linspace(-2,2,5)
# => Cumo::DFloat#shape=[5]
# [-2, -1, 0, 1, 2]

a.outer(b)
# => Cumo::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 (Cumo::NArray)
  • axis (Integer) (defaults to: nil) —

    applied axis (default=-1)

Returns:



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# File 'lib/cumo/narray/extra.rb', line 1324

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

#percentile(q, axis: nil) ⇒ Numo::NArray

Percentile

Parameters:

  • q (Numo::NArray)
  • axis (Integer) (defaults to: nil) —

    applied axis

Returns:

  • (Numo::NArray) —

    return percentile

Raises:

  • (ArgumentError) 


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# File 'lib/cumo/narray/extra.rb', line 1347

def percentile(q, axis: nil)
  raise ArgumentError, "q is out of range" if q < 0 || q > 100

  x = self
  unless axis
    axis = 0
    x = x.flatten
  end

  sorted = x.sort(axis: axis)
  x = q / 100.0 * (sorted.shape[axis] - 1)
  r = x % 1
  i = x.floor
  refs = [true] * sorted.ndim
  refs[axis] = i
  if i == sorted.shape[axis] - 1
    sorted[*refs]
  else
    refs_upper = refs.dup
    refs_upper[axis] = i + 1
    sorted[*refs] + r * (sorted[*refs_upper] - sorted[*refs])
  end
end

#rad2deg ⇒ Object

Convert angles from radians to degrees.



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# File 'lib/cumo/narray/extra.rb', line 56

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

#repeat(arg, axis: nil) ⇒ Object

Examples:

Cumo::NArray[3].repeat(4)
# => Cumo::Int32#shape=[4]
# [3, 3, 3, 3]

x = Cumo::NArray[[1,2],[3,4]]
# => Cumo::Int32#shape=[2,2]
# [[1, 2],
#  [3, 4]]

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 961

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 should 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

#rot90(k = 1, axes = [0, 1]) ⇒ Object

Rotate in the plane specified by axes.

Examples:

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

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 98

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

#set(src, stream: nil) ⇒ Object

Copies a host buffer into this array. A Cumo::CUDA::PinnedMemory is copied asynchronously on the current stream, or on stream:, and a String of bytes synchronously.



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# File 'lib/cumo/narray/extra.rb', line 8

def set(src, stream: nil)
  case src
  when Cumo::CUDA::PinnedMemory
    src.copy(self, :to_narray, stream)
  when String
    raise ArgumentError, "a String is copied synchronously, so it takes no stream:" unless stream.nil?
    store_binary(src)
  else
    raise TypeError, "set takes a Cumo::CUDA::PinnedMemory or a String, got a #{src.class}"
  end
  self
end

#split(indices_or_sections, axis: 0) ⇒ Object

Examples:

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

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 772

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

#tile(*arg) ⇒ Object

Examples:

a = Cumo::NArray[0,1,2]
# => Cumo::Int32#shape=[3]
# [0, 1, 2]

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

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

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

b = Cumo::NArray[[1, 2], [3, 4]]
# => Cumo::Int32#shape=[2,2]
# [[1, 2],
#  [3, 4]]

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

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

c = Cumo::NArray[1,2,3,4]
# => Cumo::Int32#shape=[4]
# [1, 2, 3, 4]

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


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# File 'lib/cumo/narray/extra.rb', line 900

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_c ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 129

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

#to_f ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 120

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

#to_i ⇒ Object 



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# File 'lib/cumo/narray/extra.rb', line 111

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

#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=[-2,-1].

Parameters:

  • offset (Integer) (defaults to: nil) —

    (optional, default=0) diagonal offset

  • axis (Array) (defaults to: nil) —

    (optional, default=[-2,-1]) diagonal axis

  • nan (Bool) (defaults to: false) —

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



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# File 'lib/cumo/narray/extra.rb', line 1218

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

#tril(k = 0) ⇒ Object

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



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# File 'lib/cumo/narray/extra.rb', line 1091

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.



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# File 'lib/cumo/narray/extra.rb', line 1097

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.



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# File 'lib/cumo/narray/extra.rb', line 1113

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.



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# File 'lib/cumo/narray/extra.rb', line 1052

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.



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# File 'lib/cumo/narray/extra.rb', line 1058

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 upper-triangle on and above the k-th diagonal.



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# File 'lib/cumo/narray/extra.rb', line 1074

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)
end

#vsplit(indices_or_sections) ⇒ Object

Examples:

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

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

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


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# File 'lib/cumo/narray/extra.rb', line 841

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