# scipy.signal.argrelextrema#

scipy.signal.argrelextrema(data, comparator, axis=0, order=1, mode='clip')[source]#

Calculate the relative extrema of data.

Parameters:
datandarray

Array in which to find the relative extrema.

comparatorcallable

Function to use to compare two data points. Should take two arrays as arguments.

axisint, optional

Axis over which to select from data. Default is 0.

orderint, optional

How many points on each side to use for the comparison to consider `comparator(n, n+x)` to be True.

modestr, optional

How the edges of the vector are treated. ‘wrap’ (wrap around) or ‘clip’ (treat overflow as the same as the last (or first) element). Default is ‘clip’. See `numpy.take`.

Returns:
extrematuple of ndarrays

Indices of the maxima in arrays of integers. `extrema[k]` is the array of indices of axis k of data. Note that the return value is a tuple even when data is 1-D.

Notes

Examples

```>>> import numpy as np
>>> from scipy.signal import argrelextrema
>>> x = np.array([2, 1, 2, 3, 2, 0, 1, 0])
>>> argrelextrema(x, np.greater)
(array([3, 6]),)
>>> y = np.array([[1, 2, 1, 2],
...               [2, 2, 0, 0],
...               [5, 3, 4, 4]])
...
>>> argrelextrema(y, np.less, axis=1)
(array([0, 2]), array([2, 1]))
```