median¶

pydl.median(array, width=None, axis=None, even=False)[source]¶

Replicate the IDL MEDIAN() function.

Parameters:

arrayarray-like: Compute the median of this array.
widthint, optional: Size of the neighborhood in which to compute the median (i.e., perform median filtering). If omitted, the median of the whole array is returned.
axisint, optional: Compute the median over this axis for a multi-dimensional array. If ommitted, the median over the entire array will be returned. If set, this function will behave as though even is True.
evenbool, optional: If set to True, the median of arrays with an even number of elements will be the average of the middle two values.

Returns:

Raises:

ValueError: If width is set, and the input array is not 1 or 2 dimensional.

Notes

For arrays with an even number of elements, the numpy.median() function behaves like MEDIAN(array, /EVEN), so the absence of the even keyword has to turn off that behavior.
For median filtering, this uses scipy.signal.medfilt() and scipy.signal.medfilt2d() under the hood, but patches up the values on the array boundaries to match the return values of the IDL MEDIAN() function.

References