ruby--ruby/spec/ruby/library/matrix/scalar_spec.rb

require_relative '../../spec_helper'

ruby_version_is ""..."3.1" do
  require 'matrix'

  describe "Matrix.scalar" do

    before :each do
      @side = 3
      @value = 8
      @a = Matrix.scalar(@side, @value)
    end

    it "returns a Matrix" do
      @a.should be_kind_of(Matrix)
    end

    it "returns a n x n matrix" do
      @a.row_size.should == @side
      @a.column_size.should == @side
    end

    it "initializes diagonal to value" do
      (0...@a.row_size).each do |i|
        @a[i, i].should == @value
      end
    end

    it "initializes all non-diagonal values to 0" do
      (0...@a.row_size).each do |i|
        (0...@a.column_size).each do |j|
          if i != j
            @a[i, j].should == 0
          end
        end
      end
    end

    before :each do
      @side = 3
      @value = 8
      @a = Matrix.scalar(@side, @value)
    end

    it "returns a Matrix" do
      @a.should be_kind_of(Matrix)
    end

    it "returns a square matrix, where the first argument specifies the side of the square" do
      @a.row_size.should == @side
      @a.column_size.should == @side
    end

    it "puts the second argument in all diagonal values" do
      (0...@a.row_size).each do |i|
        @a[i, i].should == @value
      end
    end

    it "fills all values not on the main diagonal with 0" do
      (0...@a.row_size).each do |i|
        (0...@a.column_size).each do |j|
          if i != j
            @a[i, j].should == 0
          end
        end
      end
    end
  end
end