diff options
Diffstat (limited to 'numpy/lib/arraysetops.py')
| -rw-r--r-- | numpy/lib/arraysetops.py | 33 |
1 files changed, 12 insertions, 21 deletions
diff --git a/numpy/lib/arraysetops.py b/numpy/lib/arraysetops.py index 6cca1738b..6c6c1ff80 100644 --- a/numpy/lib/arraysetops.py +++ b/numpy/lib/arraysetops.py @@ -1,28 +1,17 @@ """ Set operations for arrays based on sorting. -:Contains: - unique, - isin, - ediff1d, - intersect1d, - setxor1d, - in1d, - union1d, - setdiff1d - -:Notes: +Notes +----- For floating point arrays, inaccurate results may appear due to usual round-off and floating point comparison issues. Speed could be gained in some operations by an implementation of -sort(), that can provide directly the permutation vectors, avoiding -thus calls to argsort(). +`numpy.sort`, that can provide directly the permutation vectors, thus avoiding +calls to `numpy.argsort`. -To do: Optionally return indices analogously to unique for all functions. - -:Author: Robert Cimrman +Original author: Robert Cimrman """ import functools @@ -104,7 +93,7 @@ def ediff1d(ary, to_end=None, to_begin=None): else: to_begin = np.asanyarray(to_begin) if not np.can_cast(to_begin, dtype_req, casting="same_kind"): - raise TypeError("dtype of `to_end` must be compatible " + raise TypeError("dtype of `to_begin` must be compatible " "with input `ary` under the `same_kind` rule.") to_begin = to_begin.ravel() @@ -278,7 +267,7 @@ def unique(ar, return_index=False, return_inverse=False, ar = np.moveaxis(ar, axis, 0) except np.AxisError: # this removes the "axis1" or "axis2" prefix from the error message - raise np.AxisError(axis, ar.ndim) + raise np.AxisError(axis, ar.ndim) from None # Must reshape to a contiguous 2D array for this to work... orig_shape, orig_dtype = ar.shape, ar.dtype @@ -300,10 +289,10 @@ def unique(ar, return_index=False, return_inverse=False, # array with shape `(len(ar),)`. Because `dtype` in this case has # itemsize 0, the total size of the result is still 0 bytes. consolidated = np.empty(len(ar), dtype=dtype) - except TypeError: + except TypeError as e: # There's no good way to do this for object arrays, etc... msg = 'The axis argument to unique is not supported for dtype {dt}' - raise TypeError(msg.format(dt=ar.dtype)) + raise TypeError(msg.format(dt=ar.dtype)) from e def reshape_uniq(uniq): n = len(uniq) @@ -369,7 +358,9 @@ def intersect1d(ar1, ar2, assume_unique=False, return_indices=False): Input arrays. Will be flattened if not already 1D. assume_unique : bool If True, the input arrays are both assumed to be unique, which - can speed up the calculation. Default is False. + can speed up the calculation. If True but ``ar1`` or ``ar2`` are not + unique, incorrect results and out-of-bounds indices could result. + Default is False. return_indices : bool If True, the indices which correspond to the intersection of the two arrays are returned. The first instance of a value is used if there are |