Method: Stick::Matrix#**

Defined in:
lib/stick/matrix/core.rb

#**(other) ⇒ Object

Matrix exponentiation. Defined for integer powers only. Equivalent to multiplying the matrix by itself N times.

Matrix[[7,6], [3,9]] ** 2
  => 67 96
     48 99



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# File 'lib/stick/matrix/core.rb', line 655

def ** (other)
  if other.kind_of?(Integer)
    x = self
    if other <= 0
      x = self.inverse
      return Matrix.identity(self.column_size) if other == 0
      other = -other
    end
    z = x
    n = other  - 1
    while n != 0
      while (div, mod = n.divmod(2)
             mod == 0)
        x = x * x
        n = div
      end
      z *= x
      n -= 1
    end
    z
  elsif other.kind_of?(Float) || defined?(Rational) && other.kind_of?(Rational)
    Matrix.Raise ErrOperationNotDefined, "**"
  else
    Matrix.Raise ErrOperationNotDefined, "**"
  end
end