xarray.ufuncs.sign = <xarray.ufuncs._UFuncDispatcher object>

xarray specific variant of numpy.sign. Handles xarray.Dataset, xarray.DataArray, xarray.Variable, numpy.ndarray and dask.array.Array objects with automatic dispatching.

Documentation from numpy:

sign(x[, out])

Returns an element-wise indication of the sign of a number.

The sign function returns -1 if x < 0, 0 if x==0, 1 if x > 0. nan is returned for nan inputs.

For complex inputs, the sign function returns sign(x.real) + 0j if x.real != 0 else sign(x.imag) + 0j.

complex(nan, 0) is returned for complex nan inputs.


x : array_like

Input values.


y : ndarray

The sign of x.


There is more than one definition of sign in common use for complex numbers. The definition used here is equivalent to \(x/\sqrt{x*x}\) which is different from a common alternative, \(x/|x|\).


>>> np.sign([-5., 4.5])
array([-1.,  1.])
>>> np.sign(0)
>>> np.sign(5-2j)