title: Finding a local Maxima/minimum using python
body: <p>My code is based on a comment in:
  <a href="https://stackoverflow.com/questions/4624970/finding-local-maxima-minima-with-numpy-in-a-1d-numpy-array">Finding local maxima/minima with Numpy in a 1D numpy array</a></p>
  
  <p>It works, however it does not reproduce all the peaks for me. It always seems to miss the first peak. Is there any way to make this code a bit more robust in determining each peak?</p>
  
  <p>I have tried smoothing the data, changing the order etc to no avail.</p>
  
  <pre><code>import numpy as np
  from scipy.signal import argrelextrema
  
  profile1 = "data posted below"
  
  profile1_filtered = ndimage.filters.gaussian_filter(profile1, 1, mode='nearest')
  
  plot(profile1_filtered[300:740])
  
  # for local maxima
  result = argrelextrema(profile1[300:740], np.greater, order =15)
  
  print result
  
  for i in result:
      plot([i,i],[-16380,-16300], color='k', linestyle='--', linewidth=1)
  </code></pre>
  
  <p>Thanks in advance for any help/advice!</p>
  
  <p>As I am in work, my upload/download is very restricted. Usually I would post a link to my data, however I hope this will do:
  (i will amend this with a link to my data when I get home later)</p>
  
  <pre><code>array([-16368, -16366, -16365, -16369, -16366, -16369, -16368, -16362,
         -16368, -16366, -16367, -16364, -16367, -16367, -16367, -16366,
         -16363, -16366, -16369, -16370, -16365, -16364, -16362, -16363,
         -16365, -16363, -16364, -16362, -16361, -16362, -16364, -16364,
         -16365, -16361, -16363, -16363, -16366, -16361, -16360, -16363,
         -16362, -16362, -16357, -16360, -16359, -16362, -16359, -16359,
         -16358, -16358, -16355, -16356, -16355, -16349, -16350, -16349,
         -16343, -16338, -16332, -16329, -16329, -16339, -16339, -16348,
         -16351, -16351, -16354, -16355, -16355, -16356, -16357, -16355,
         -16355, -16356, -16356, -16358, -16354, -16355, -16356, -16357,
         -16356, -16355, -16355, -16352, -16357, -16353, -16353, -16352,
         -16357, -16351, -16347, -16347, -16345, -16342, -16332, -16321,
         -16315, -16311, -16315, -16320, -16327, -16335, -16341, -16346,
         -16347, -16349, -16350, -16350, -16347, -16351, -16354, -16354,
         -16352, -16353, -16352, -16354, -16356, -16354, -16358, -16354,
         -16353, -16356, -16351, -16352, -16351, -16351, -16352, -16347,
         -16344, -16344, -16340, -16335, -16326, -16315, -16305, -16299,
         -16303, -16309, -16322, -16331, -16335, -16342, -16342, -16346,
         -16349, -16353, -16352, -16350, -16350, -16350, -16354, -16353,
         -16353, -16355, -16355, -16356, -16353, -16352, -16352, -16356,
         -16354, -16354, -16354, -16353, -16354, -16352, -16355, -16349,
         -16350, -16347, -16346, -16342, -16338, -16334, -16338, -16335,
         -16341, -16344, -16345, -16349, -16349, -16349, -16353, -16353,
         -16353, -16353, -16354, -16353, -16351, -16351, -16352, -16354,
         -16353, -16353, -16353, -16355, -16354, -16352, -16353, -16356,
         -16354, -16353, -16353, -16353, -16352, -16349, -16350, -16347,
         -16345, -16340, -16337, -16331, -16332, -16329, -16337, -16339,
         -16342, -16344, -16345, -16348, -16351, -16351, -16350, -16352,
         -16351, -16346, -16353, -16349, -16350, -16352, -16353, -16349,
         -16352, -16351, -16354, -16352, -16354, -16352, -16354, -16352,
         -16354, -16349, -16348, -16347, -16347, -16343, -16343, -16338,
         -16333, -16330, -16331, -16336, -16340, -16341, -16345, -16346,
         -16347, -16346, -16348, -16352, -16350, -16349, -16351, -16351,
         -16354, -16353, -16353, -16355, -16351, -16352, -16353, -16354,
         -16351, -16353, -16351, -16352, -16349, -16351, -16350, -16351,
         -16352, -16348, -16352, -16349, -16345, -16346, -16341, -16337,
         -16338, -16339, -16342, -16346, -16344, -16348, -16352, -16350,
         -16352, -16353, -16350, -16353, -16356, -16355, -16356, -16354,
         -16352, -16357, -16355, -16356, -16353, -16352, -16354, -16356,
         -16355, -16358, -16352, -16352, -16353, -16351, -16353, -16350,
         -16350, -16349, -16351, -16346, -16344, -16340, -16339, -16338,
         -16339, -16343, -16344, -16345, -16348, -16351, -16350, -16351,
         -16353, -16354, -16353, -16350, -16353, -16354, -16352, -16355,
         -16353, -16356, -16353, -16354, -16356, -16352, -16353, -16355,
         -16353, -16353, -16351, -16352, -16354, -16349, -16349, -16349,
         -16348, -16343, -16340, -16334, -16323, -16322, -16326, -16328,
         -16334, -16343, -16347, -16349, -16348, -16350, -16353, -16353,
         -16354, -16354, -16357, -16356, -16353, -16354, -16358, -16356,
         -16354, -16357, -16357, -16358, -16356, -16357, -16356, -16354,
         -16355, -16356, -16354, -16355, -16353, -16352, -16351, -16351,
         -16346, -16342, -16336, -16333, -16334, -16336, -16342, -16345,
         -16347, -16354, -16354, -16357, -16358, -16359, -16359, -16362,
         -16361, -16360, -16361, -16360, -16363, -16362, -16362, -16364,
         -16363, -16363, -16363, -16363, -16364, -16363, -16364, -16366,
         -16365, -16363, -16362, -16365, -16366, -16364, -16368, -16367])
  </code></pre>