Method: NMatrix.random

Defined in:
lib/nmatrix/shortcuts.rb

.random(shape, opts = {}) ⇒ Object Also known as: rand

call-seq:

random(shape) -> NMatrix

Creates a :dense NMatrix with random numbers between 0 and 1 generated by Random::rand. The parameter is the dimension of the matrix.

If you use an integer dtype, make sure to specify :scale as a parameter, or you’ll only get a matrix of 0s.

  • Arguments :

    • shape -> Array (or integer for square matrix) specifying the dimensions.

  • Returns :

    • NMatrix filled with random values.

Examples:

NMatrix.random([2, 2]) # => 0.4859439730644226   0.1783195585012436
                            0.23193766176700592  0.4503345191478729

NMatrix.random([2, 2], :dtype => :byte, :scale => 255) # => [ [252, 108] [44, 12] ]



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# File 'lib/nmatrix/shortcuts.rb', line 370

def random(shape, opts={})
  scale = opts.delete(:scale) || 1.0

  rng = Random.new

  random_values = []


  # Construct the values of the final matrix based on the dimension.
  if opts[:dtype] == :complex64 || opts[:dtype] == :complex128
    NMatrix.size(shape).times { |i| random_values << Complex(rng.rand(scale), rng.rand(scale)) }
  else
    NMatrix.size(shape).times { |i| random_values << rng.rand(scale) }
  end

  NMatrix.new(shape, random_values, {:dtype => :float64, :stype => :dense}.merge(opts))
end