diff options
Diffstat (limited to 'numpy/lib/nanfunctions.py')
| -rw-r--r-- | numpy/lib/nanfunctions.py | 90 |
1 files changed, 63 insertions, 27 deletions
diff --git a/numpy/lib/nanfunctions.py b/numpy/lib/nanfunctions.py index b3bf1880b..8e2a34e70 100644 --- a/numpy/lib/nanfunctions.py +++ b/numpy/lib/nanfunctions.py @@ -40,6 +40,33 @@ __all__ = [ ] +def _nan_mask(a, out=None): + """ + Parameters + ---------- + a : array-like + Input array with at least 1 dimension. + out : ndarray, optional + Alternate output array in which to place the result. The default + is ``None``; if provided, it must have the same shape as the + expected output and will prevent the allocation of a new array. + + Returns + ------- + y : bool ndarray or True + A bool array where ``np.nan`` positions are marked with ``False`` + and other positions are marked with ``True``. If the type of ``a`` + is such that it can't possibly contain ``np.nan``, returns ``True``. + """ + # we assume that a is an array for this private function + + if a.dtype.kind not in 'fc': + return True + + y = np.isnan(a, out=out) + y = np.invert(y, out=y) + return y + def _replace_nan(a, val): """ If `a` is of inexact type, make a copy of `a`, replace NaNs with @@ -68,17 +95,18 @@ def _replace_nan(a, val): NaNs, otherwise return None. """ - a = np.array(a, subok=True, copy=True) + a = np.asanyarray(a) if a.dtype == np.object_: # object arrays do not support `isnan` (gh-9009), so make a guess - mask = a != a + mask = np.not_equal(a, a, dtype=bool) elif issubclass(a.dtype.type, np.inexact): mask = np.isnan(a) else: mask = None if mask is not None: + a = np.array(a, subok=True, copy=True) np.copyto(a, val, where=mask) return a, mask @@ -138,7 +166,8 @@ def _remove_nan_1d(arr1d, overwrite_input=False): c = np.isnan(arr1d) s = np.nonzero(c)[0] if s.size == arr1d.size: - warnings.warn("All-NaN slice encountered", RuntimeWarning, stacklevel=4) + warnings.warn("All-NaN slice encountered", RuntimeWarning, + stacklevel=5) return arr1d[:0], True elif s.size == 0: return arr1d, overwrite_input @@ -216,8 +245,8 @@ def nanmin(a, axis=None, out=None, keepdims=np._NoValue): out : ndarray, optional Alternate output array in which to place the result. The default is ``None``; if provided, it must have the same shape as the - expected output, but the type will be cast if necessary. See - `doc.ufuncs` for details. + expected output, but the type will be cast if necessary. See + `ufuncs-output-type` for more details. .. versionadded:: 1.8.0 keepdims : bool, optional @@ -291,7 +320,8 @@ def nanmin(a, axis=None, out=None, keepdims=np._NoValue): # which do not implement isnan (gh-9009), or fmin correctly (gh-8975) res = np.fmin.reduce(a, axis=axis, out=out, **kwargs) if np.isnan(res).any(): - warnings.warn("All-NaN slice encountered", RuntimeWarning, stacklevel=2) + warnings.warn("All-NaN slice encountered", RuntimeWarning, + stacklevel=3) else: # Slow, but safe for subclasses of ndarray a, mask = _replace_nan(a, +np.inf) @@ -303,7 +333,8 @@ def nanmin(a, axis=None, out=None, keepdims=np._NoValue): mask = np.all(mask, axis=axis, **kwargs) if np.any(mask): res = _copyto(res, np.nan, mask) - warnings.warn("All-NaN axis encountered", RuntimeWarning, stacklevel=2) + warnings.warn("All-NaN axis encountered", RuntimeWarning, + stacklevel=3) return res @@ -329,8 +360,8 @@ def nanmax(a, axis=None, out=None, keepdims=np._NoValue): out : ndarray, optional Alternate output array in which to place the result. The default is ``None``; if provided, it must have the same shape as the - expected output, but the type will be cast if necessary. See - `doc.ufuncs` for details. + expected output, but the type will be cast if necessary. See + `ufuncs-output-type` for more details. .. versionadded:: 1.8.0 keepdims : bool, optional @@ -404,7 +435,8 @@ def nanmax(a, axis=None, out=None, keepdims=np._NoValue): # which do not implement isnan (gh-9009), or fmax correctly (gh-8975) res = np.fmax.reduce(a, axis=axis, out=out, **kwargs) if np.isnan(res).any(): - warnings.warn("All-NaN slice encountered", RuntimeWarning, stacklevel=2) + warnings.warn("All-NaN slice encountered", RuntimeWarning, + stacklevel=3) else: # Slow, but safe for subclasses of ndarray a, mask = _replace_nan(a, -np.inf) @@ -416,7 +448,8 @@ def nanmax(a, axis=None, out=None, keepdims=np._NoValue): mask = np.all(mask, axis=axis, **kwargs) if np.any(mask): res = _copyto(res, np.nan, mask) - warnings.warn("All-NaN axis encountered", RuntimeWarning, stacklevel=2) + warnings.warn("All-NaN axis encountered", RuntimeWarning, + stacklevel=3) return res @@ -553,8 +586,8 @@ def nansum(a, axis=None, dtype=None, out=None, keepdims=np._NoValue): Alternate output array in which to place the result. The default is ``None``. If provided, it must have the same shape as the expected output, but the type will be cast if necessary. See - `doc.ufuncs` for details. The casting of NaN to integer can yield - unexpected results. + `ufuncs-output-type` for more details. The casting of NaN to integer + can yield unexpected results. .. versionadded:: 1.8.0 keepdims : bool, optional @@ -649,9 +682,9 @@ def nanprod(a, axis=None, dtype=None, out=None, keepdims=np._NoValue): out : ndarray, optional Alternate output array in which to place the result. The default is ``None``. If provided, it must have the same shape as the - expected output, but the type will be cast if necessary. See - `doc.ufuncs` for details. The casting of NaN to integer can yield - unexpected results. + expected output, but the type will be cast if necessary. See + `ufuncs-output-type` for more details. The casting of NaN to integer + can yield unexpected results. keepdims : bool, optional If True, the axes which are reduced are left in the result as dimensions with size one. With this option, the result will @@ -718,8 +751,8 @@ def nancumsum(a, axis=None, dtype=None, out=None): out : ndarray, optional Alternative output array in which to place the result. It must have the same shape and buffer length as the expected output - but the type will be cast if necessary. See `doc.ufuncs` - (Section "Output arguments") for more details. + but the type will be cast if necessary. See `ufuncs-output-type` for + more details. Returns ------- @@ -856,8 +889,8 @@ def nanmean(a, axis=None, dtype=None, out=None, keepdims=np._NoValue): out : ndarray, optional Alternate output array in which to place the result. The default is ``None``; if provided, it must have the same shape as the - expected output, but the type will be cast if necessary. See - `doc.ufuncs` for details. + expected output, but the type will be cast if necessary. See + `ufuncs-output-type` for more details. keepdims : bool, optional If this is set to True, the axes which are reduced are left in the result as dimensions with size one. With this option, @@ -920,7 +953,7 @@ def nanmean(a, axis=None, dtype=None, out=None, keepdims=np._NoValue): isbad = (cnt == 0) if isbad.any(): - warnings.warn("Mean of empty slice", RuntimeWarning, stacklevel=2) + warnings.warn("Mean of empty slice", RuntimeWarning, stacklevel=3) # NaN is the only possible bad value, so no further # action is needed to handle bad results. return avg @@ -932,7 +965,7 @@ def _nanmedian1d(arr1d, overwrite_input=False): See nanmedian for parameter usage """ arr1d, overwrite_input = _remove_nan_1d(arr1d, - overwrite_input=overwrite_input) + overwrite_input=overwrite_input) if arr1d.size == 0: return np.nan @@ -975,7 +1008,8 @@ def _nanmedian_small(a, axis=None, out=None, overwrite_input=False): a = np.ma.masked_array(a, np.isnan(a)) m = np.ma.median(a, axis=axis, overwrite_input=overwrite_input) for i in range(np.count_nonzero(m.mask.ravel())): - warnings.warn("All-NaN slice encountered", RuntimeWarning, stacklevel=3) + warnings.warn("All-NaN slice encountered", RuntimeWarning, + stacklevel=4) if out is not None: out[...] = m.filled(np.nan) return out @@ -1224,6 +1258,7 @@ def nanquantile(a, q, axis=None, out=None, overwrite_input=False, Compute the qth quantile of the data along the specified axis, while ignoring nan values. Returns the qth quantile(s) of the array elements. + .. versionadded:: 1.15.0 Parameters @@ -1409,7 +1444,7 @@ def nanvar(a, axis=None, dtype=None, out=None, ddof=0, keepdims=np._NoValue): the variance of the flattened array. dtype : data-type, optional Type to use in computing the variance. For arrays of integer type - the default is `float32`; for arrays of float types it is the same as + the default is `float64`; for arrays of float types it is the same as the array type. out : ndarray, optional Alternate output array in which to place the result. It must have @@ -1439,7 +1474,7 @@ def nanvar(a, axis=None, dtype=None, out=None, ddof=0, keepdims=np._NoValue): mean : Average var : Variance while not ignoring NaNs nanstd, nanmean - numpy.doc.ufuncs : Section "Output arguments" + ufuncs-output-type Notes ----- @@ -1520,7 +1555,8 @@ def nanvar(a, axis=None, dtype=None, out=None, ddof=0, keepdims=np._NoValue): isbad = (dof <= 0) if np.any(isbad): - warnings.warn("Degrees of freedom <= 0 for slice.", RuntimeWarning, stacklevel=2) + warnings.warn("Degrees of freedom <= 0 for slice.", RuntimeWarning, + stacklevel=3) # NaN, inf, or negative numbers are all possible bad # values, so explicitly replace them with NaN. var = _copyto(var, np.nan, isbad) @@ -1590,7 +1626,7 @@ def nanstd(a, axis=None, dtype=None, out=None, ddof=0, keepdims=np._NoValue): -------- var, mean, std nanvar, nanmean - numpy.doc.ufuncs : Section "Output arguments" + ufuncs-output-type Notes ----- |