require_relative '../../../spec_helper' require 'matrix' describe "Matrix::LUPDecomposition#l" do before :each do @a = Matrix[[7, 8, 9], [14, 46, 51], [28, 82, 163]] @lu = Matrix::LUPDecomposition.new(@a) @l = @lu.l end it "returns the first element of to_a" do @l.should == @lu.to_a[0] end it "returns a lower triangular matrix" do @l.lower_triangular?.should be_true end end