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Finding Relative Maxima in Python3

0 votes

The last few days I've been working on a script to manipulate some scientific data. One thing I would like to be able to do is find relative maxima in a data set.
I'm using numpy in python3 (which I think I can't do without because of utf16 encoding of my data source) and a series of np.arrays. When looking around the web and some forums I came across the scipy function argrelextrema, which seemed to do just what I wanted. The problem is that I can't get the function to work, probably because scipy in python3 does not yet support the argrelextrema function. I can however, not find a reference to this really being the problem, and was wondering if someone here could maybe help me out.
The code I used is shown below. The function to return the maximum values is called by a different script. Then, when running, it returns an error like the one below the code.

import numpy as np
import scipy as sp

def max_in_array_range(MaxArray, Column, LowBound):

 "Finding the max value an array with a predefined in a certain column and from a threshold index.
 The complete array is loaded through Max Array. The column is first selected. 
 The, the LowBound is called (the data is only interesting from a certain point onward."
 TempArray = MaxArray[:, Column] # Creation of Temporary Array to ensure 1D Array and specification of the LowBound in the next line.
 return sp.argrelextrema(TempArray[LowBound:], np.greater)

Error message:
Traceback (most recent call last):
 File "", line 15, in 
 Varrr = FD.max_in_array_range(CalcAndDiffArray, 5 ,MyBound)
 File "/MyPath/", line 82, in max_in_array_range
 return sp.argrelmax(TempArray[LowBound:], np.greater)
AttributeError: 'module' object has no attribute 'argrelmax'
posted May 31, 2013 by anonymous

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1 Answer

0 votes

he docs would seem to indicate that that function resides in the "signal" submodule of scipy:
Hence, it would be sp.signal.argrelmax() as opposed to just sp.argrelmax()

answer May 31, 2013 by anonymous
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