def test_safe_dtype():
yield assert_raises, TypeError, safe_dtype, type('foo')
yield assert_raises, TypeError, safe_dtype, type('foo'), np.float64
yield assert_raises, TypeError, safe_dtype, [('x', 'f8')]
valid_dtypes = []
valid_dtypes.extend(np.sctypes['complex'])
valid_dtypes.extend(np.sctypes['float'])
valid_dtypes.extend(np.sctypes['int'])
valid_dtypes.extend(np.sctypes['uint'])
for dt in valid_dtypes:
sdt = safe_dtype(dt)
yield assert_equal, sdt, dt
# test a few upcastings
dt = safe_dtype(np.float32, np.int16, np.bool)
yield assert_equal, dt, np.float32
dt = safe_dtype(np.float32, np.int64, np.uint32)
yield assert_equal, dt, np.float64
def test_safe_dtype():
yield assert_raises, TypeError, safe_dtype, type('foo')
yield assert_raises, TypeError, safe_dtype, type('foo'), np.float64
yield assert_raises, TypeError, safe_dtype, [('x', 'f8')]
valid_dtypes = []
valid_dtypes.extend(np.sctypes['complex'])
valid_dtypes.extend(np.sctypes['float'])
valid_dtypes.extend(np.sctypes['int'])
valid_dtypes.extend(np.sctypes['uint'])
for dt in valid_dtypes:
sdt = safe_dtype(dt)
yield assert_equal, sdt, dt
# test a few upcastings
dt = safe_dtype(np.float32, np.int16, np.bool)
yield assert_equal, dt, np.float32
dt = safe_dtype(np.float32, np.int64, np.uint32)
yield assert_equal, dt, np.float64
# test byteswapped types - isbuiltin will be false
orig_dt = np.dtype('f')
dt = safe_dtype(orig_dt, np.int64, np.uint32)
yield assert_equal, dt, np.float64
swapped_dt = orig_dt.newbyteorder()
dt = safe_dtype(swapped_dt, np.int64, np.uint32)
yield assert_equal, dt, np.float64
def __init__(self, affine, input_coords, output_coords):
"""
Return an CoordinateMap specified by an affine transformation
in homogeneous coordinates.
Parameters
----------
affine : array-like
affine homogenous coordinate matrix
input_coords : :class:`CoordinateSystem`
input coordinates
output_coords : :class:`CoordinateSystem`
output coordinates
Notes
-----
The dtype of the resulting matrix is determined by finding a
safe typecast for the input_coords, output_coords and affine.
"""
affine = np.asarray(affine)
dtype = safe_dtype(affine.dtype,
input_coords.coord_dtype,
output_coords.coord_dtype)
inaxes = input_coords.coord_names
outaxes = output_coords.coord_names
self._input_coords = CoordinateSystem(inaxes,
input_coords.name,
dtype)
self._output_coords = CoordinateSystem(outaxes,
output_coords.name,
dtype)
affine = np.asarray(affine, dtype=dtype)
if affine.shape != (self.ndim[1]+1, self.ndim[0]+1):
raise ValueError('coordinate lengths do not match '
'affine matrix shape')
self._affine = affine
A, b = affines.to_matrix_vector(affine)
def _mapping(x):
value = np.dot(x, A.T)
value += b
return value
self._mapping = _mapping
