def test_scaling():
# Test integer scaling from float
# Analyze headers cannot do float-integer scaling '''
hdr = AnalyzeHeader()
yield assert_true, hdr.default_x_flip
shape = (1,2,3)
hdr.set_data_shape(shape)
hdr.set_data_dtype(np.float32)
data = np.ones(shape, dtype=np.float64)
S = StringIO()
# Writing to float datatype doesn't need scaling
write_scaled_data(hdr, data, S)
rdata = read_data(hdr, S)
yield assert_true, np.allclose(data, rdata)
# Writing to integer datatype does, and raises an error
hdr.set_data_dtype(np.int32)
yield (assert_raises, HeaderTypeError, write_scaled_data,
hdr, data, StringIO())
# unless we aren't scaling, in which case we convert the floats to
# integers and write
write_data(hdr, data, S)
rdata = read_data(hdr, S)
yield assert_true, np.allclose(data, rdata)
# This won't work for floats that aren't close to integers
data_p5 = data + 0.5
write_data(hdr, data_p5, S)
rdata = read_data(hdr, S)
yield assert_false, np.allclose(data_p5, rdata)
def test_best_affine():
hdr = AnalyzeHeader()
hdr.set_data_shape((3,5,7))
hdr.set_zooms((4,5,6))
yield assert_array_equal, hdr.get_base_affine(), hdr.get_best_affine()