require_relative '../../spec_helper'

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

  describe "Matrix#[]" do

    before :all do
      @m = Matrix[[0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10, 11]]
    end

    it "returns element at (i, j)" do
      (0..3).each do |i|
        (0..2).each do |j|
          @m[i, j].should == (i * 3) + j
        end
      end
    end

    it "returns nil for an invalid index pair" do
      @m[8,1].should be_nil
      @m[1,8].should be_nil
    end

  end
end
