code: def test_array_sub():
      d0, d1, d2, d3 = random_shape(4)
      x = np.random.rand(d0, d1, d2, d3) - 0.5
      y = (100 * np.random.rand(d0, d1, d2, d3)).astype("uint8")
      _test_array_sub(x, y)
  
file_path: nipy/nipy/labs/bindings/tests/test_array.py
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_array_equal
  from ..None import array_add, array_div, array_get, array_get_block, array_mul, array_sub
label_desc: Use image node_id 11 for calling a global function with example usage: test_array_sub() without return types