# scipy.signal.argrelextrema¶

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

Calculate the relative extrema of data.

New in version 0.11.0.

Parameters: data : ndarray Array in which to find the relative extrema. comparator : callable Function to use to compare two data points. Should take 2 numbers as arguments. axis : int, optional Axis over which to select from data. Default is 0. order : int, optional How many points on each side to use for the comparison to consider comparator(n, n+x) to be True. mode : str, 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. extrema : tuple 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 one-dimensional.

Examples

```>>> 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]))
```

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