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I am trying to plot profiles from an interpolated data. To begin with my data is three columns x,y,c.

First I interpolate the data onto a regular grid using:

  xi , yi = np.linspace(np.min(X), np.max(X),300) , np.linspace(np.min(Y), np.max(Y),300)
  xi, yi = np.meshgrid(xi, yi)
  zi = scipy.interpolate.griddata((X, Y), C , (xi, yi),method='nearest')

now following the thread: How to extract an arbitrary line of values from a numpy array?

I want to plot the values at X = 5 for Y = -4,4

  x0, y0 = 5, -4 # These are in _pixel_ coordinates!!
  x1, y1 = 5, 4
  num = 50
  x, y = np.linspace(x0, x1, num), np.linspace(y0, y1, num)
  #Getting values at that location
  zi2 = scipy.ndimage.map_coordinates(np.transpose(zi), np.vstack((x,y)))
  #Plotting 

  fig, axes = plt.subplots(nrows=2)
  axes[0].imshow(zi, vmin=np.min(C), vmax=110, origin='lower',extent=      [np.min(X), np.max(X), np.min(Y), np.max(Y)])
  axes[0].plot([x0, x1], [y0, y1], 'ro-')
  axes[0].axis('image')

  axes[1].plot(y,zi2)

  plt.show()

I get the following plot which is not looking the same as the way contour is behaving.

plot output

DSM
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Krishna Ravi
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    At first glance you may be mixing up x,y with row, column. Keep in mind that X corresponds to columns, and Y to rows, so `map_coordinates` expects , not . – Joe Kington Mar 13 '15 at 00:22

0 Answers0