Method: RMath3D::RMtx2#initialize

Defined in:
lib/rmath3d/rmath3d_plain.rb

#initialize(*a) ⇒ RMtx2

call-seq:

RMtx2.new -> ((1,0),(0,1))
RMtx2.new(e) -> ((e,e), (e,e))
RMtx2.new( other ) : Copy Constructor
RMtx2.new( e0, e1, e2, e3 ) -> ((e0,e1), (e2,e3))

Creates a new 2x2 matrix.



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# File 'lib/rmath3d/rmath3d_plain.rb', line 23

def initialize( *a )
  # [NOTE] elemetns are stored in column-major order.
  @e = []
  case a.length
  when 0
    @e = [ 0.0, 0.0,
           0.0, 0.0 ]
  when 1
    case a[0]
    when Fixnum, Float
      @e = [ a[0], a[0],
             a[0], a[0] ]
    when RMtx2
      # Copy Constructor
      @e = [ a[0].e00, a[0].e10,
             a[0].e01, a[0].e11 ]
    else
      raise TypeError, "RMtx2#initialize : Unknown type #{a[0].class}."
      return nil
    end
  when 4
    # Element-wise setter
    for row in 0...2 do
      for col in 0...2 do
        index = 2*row + col
        case a[index]
        when Fixnum, Float
          setElement( row, col, a[index] )
        else
          raise TypeError, "RMtx2#initialize : Unknown type #{a[0].class}."
          return nil
        end
      end
    end
  else
    raise RuntimeError, "RMtx2#initialize : wrong # of arguments (#{a.length})"
    return nil
  end

  return self
end