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

require_relative '../../spec_helper'

ruby_version_is ""..."3.1" do
  require_relative 'fixtures/classes'
  require 'matrix'

  describe "Matrix.columns" do
    before :each do
      @a = [1, 2]
      @b = [3, 4]
      @m = Matrix.columns([@a, @b])
    end

    it "creates a Matrix from argument columns" do
      @m.should be_an_instance_of(Matrix)
      @m.column(0).to_a.should == @a
      @m.column(1).to_a.should == @b
    end

    it "accepts Vectors as argument columns" do
      m = Matrix.columns([Vector[*@a], Vector[*@b]])
      m.should == @m
      m.column(0).to_a.should == @a
      m.column(1).to_a.should == @b
    end

    it "handles empty matrices" do
      e = Matrix.columns([])
      e.row_size.should == 0
      e.column_size.should == 0
      e.should == Matrix[]

      v = Matrix.columns([[],[],[]])
      v.row_size.should == 0
      v.column_size.should == 3
      v.should == Matrix[[], [], []].transpose
    end

    describe "for a subclass of Matrix" do
      it "returns an instance of that subclass" do
        MatrixSub.columns([[1]]).should be_an_instance_of(MatrixSub)
      end
    end
  end
end