cupyx.scipy.signal.argrelextrema#

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

Calculate the relative extrema of data.

Parameters:

  • data (ndarray) – Array in which to find the relative extrema.

  • comparator (callable) – Function to use to compare two data points. Should take two arrays 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. Available options are ‘wrap’ (wrap around) or ‘clip’ (treat overflow as the same as the last (or first) element). Default ‘clip’. See cupy.take.

Returns:

extrema – 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.

Return type:

tuple of ndarrays

See also

argrelmin, argrelmax

Examples

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