Shape Manipulation

class MDArrayTest < Test::Unit::TestCase

context "Shape Manipulation" do

setup do 

  # create an int array with 15 elements and 1 dimension
  # [0 1 2 3 4 5 6 7 8 9 10 11 12 13 14]
  @a = MDArray.arange(15)
  assert_equal([15], @a.shape)
  assert_equal(1, @a.ndim)
  assert_equal(1, @a.rank)
  assert_equal(15, @a.size)
  assert_equal("int", @a.dtype)

end

#-------------------------------------------------------------------------------------
#
#-------------------------------------------------------------------------------------

should "allow getting a section from an array" do

  b = @a.reshape([3, 5])
  c = b.section([0, 0], [3, 1])
  # c.print
  c = b.section([0, 1], [3, 1])
  # c.print
  c = b.section([0, 2], [3, 1])
  # c.print

end

#-------------------------------------------------------------------------------------
#
#-------------------------------------------------------------------------------------

should "allow array reshaping" do

  # reshape the array in place
  # [[0 1 2 3 4]
  # [5 6 7 8 9]
  # [10 11 12 13 14]]
  @a.reshape!([3, 5])
  assert_equal(2, @a.ndim)
  assert_equal([3, 5], @a.shape)
  assert_equal(0, @a[0, 0])
  assert_equal(5, @a[1, 0])
  assert_equal(12, @a[2, 2])
  assert_raise ( RuntimeError ) { @a[3, 4] }
  
  # reshape the array without copy
  b = @a.reshape([15])
  b[0] = 15
  assert_equal(15, b[0])
  assert_equal(15, @a[0, 0])

  # reshape the array with copy
  c = b.reshape([3, 5], true)
  assert_equal(15, c[0, 0])
  c[0, 1] = 20
  assert_equal(20, c[0, 1])
  assert_equal(1, b[1])

end

end

end