numpy.nanmin#
- numpy.nanmin(a,axis=None,out=None,keepdims=<novalue>,initial=<novalue>,where=<novalue>)[source]#
Return minimum of an array or minimum along an axis, ignoring any NaNs.When all-NaN slices are encountered a
RuntimeWarningis raised andNan is returned for that slice.- Parameters:
- aarray_like
Array containing numbers whose minimum is desired. Ifa is not anarray, a conversion is attempted.
- axis{int, tuple of int, None}, optional
Axis or axes along which the minimum is computed. The default is to computethe minimum of the flattened array.
- outndarray, optional
Alternate output array in which to place the result. The defaultis
None; if provided, it must have the same shape as theexpected output, but the type will be cast if necessary. SeeOutput type determination for more details.- keepdimsbool, optional
If this is set to True, the axes which are reduced are leftin the result as dimensions with size one. With this option,the result will broadcast correctly against the originala.
If the value is anything but the default, thenkeepdims will be passed through to the
minmethodof sub-classes ofndarray. If the sub-classes methodsdoes not implementkeepdims any exceptions will be raised.- initialscalar, optional
The maximum value of an output element. Must be present to allowcomputation on empty slice. See
reducefor details.New in version 1.22.0.
- wherearray_like of bool, optional
Elements to compare for the minimum. See
reducefor details.New in version 1.22.0.
- Returns:
- nanminndarray
An array with the same shape asa, with the specified axisremoved. Ifa is a 0-d array, or if axis is None, an ndarrayscalar is returned. The same dtype asa is returned.
See also
nanmaxThe maximum value of an array along a given axis, ignoring any NaNs.
aminThe minimum value of an array along a given axis, propagating any NaNs.
fminElement-wise minimum of two arrays, ignoring any NaNs.
minimumElement-wise minimum of two arrays, propagating any NaNs.
isnanShows which elements are Not a Number (NaN).
isfiniteShows which elements are neither NaN nor infinity.
amax,fmax,maximum
Notes
NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic(IEEE 754). This means that Not a Number is not equivalent to infinity.Positive infinity is treated as a very large number and negativeinfinity is treated as a very small (i.e. negative) number.
If the input has a integer type the function is equivalent to np.min.
Examples
>>>importnumpyasnp>>>a=np.array([[1,2],[3,np.nan]])>>>np.nanmin(a)1.0>>>np.nanmin(a,axis=0)array([1., 2.])>>>np.nanmin(a,axis=1)array([1., 3.])
When positive infinity and negative infinity are present:
>>>np.nanmin([1,2,np.nan,np.inf])1.0>>>np.nanmin([1,2,np.nan,-np.inf])-inf