Contourf( )

_R_Mitra · November 2, 2009, 5:45pm

Hello All
Thanks a lot Eric. I think I have some module missing but I cannot figure out what it is. I get the following. Any idea. This started hapening after I reinstalled matplotlib.

   File "/Users/Kennel/Pythoncodes/coolingmodel.py", line 6, in <module>
     import matplotlib
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/__init__.py", line 129, in <module>
     from rcsetup import defaultParams, validate_backend, validate_toolbar
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/rcsetup.py", line 19, in <module>
     from matplotlib.colors import is_color_like
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/colors.py", line 54, in <module>
     import matplotlib.cbook as cbook
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/cbook.py", line 10, in <module>
     import numpy.ma as ma
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy/ma/__init__.py", line 47, in <module>
     import extras
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy/ma/extras.py", line 45, in <module>
     from numpy.lib.index_tricks import AxisConcatenator
ImportError: cannot import name AxisConcatenator

The first few lines of my codes are:

from math import *
import exceptions
import pmag
import matplotlib
matplotlib.use("TkAgg")
import numpy as np
import matplotlib.pyplot as plt

Thanks a lot for all your help.

Mitra

···

On Nov 1, 2009, at 11:32 PM, Eric Firing wrote:

R. Mitra wrote:

Hi Eric
from math import *
import matplotlib
matplotlib.use("TkAgg")
from pylab import *
This is very basic I know. The above are the modules I am using. Is plt a separate module? Thanks.

With your method above, you don't need the "plt." part. "from pylab import *" is discouraged, however, except for quick interactive use. For scripts, it is generally considered better practice to use

import matplotlib
matplotlib.use("tkagg")
import numpy as np
import matplotlib.pyplot as plt

pyplot is the plot-related part of the pylab namespace; or to put it another way, pylab is pyplot plus numpy.

See http://matplotlib.sourceforge.net/faq/usage_faq.html

Eric

RM
On Nov 1, 2009, at 7:26 PM, Eric Firing wrote:

R. Mitra wrote:

Hi
I am having problems with contourf(). Suppose I have two 10X30 arrays X,Y and a corresponding Z value array. How do I make the upper left to be the origin? I cannot use contour (Z,origin='upper') because the axis values gets messed up.

It sounds like maybe you want to reverse the y-axis. Try something like plt.gca().invert_yaxis() after your call to contourf.

Eric

Eric_Firing1 · November 2, 2009, 5:55pm

R. Mitra wrote:

Hello All
Thanks a lot Eric. I think I have some module missing but I cannot figure out what it is. I get the following. Any idea. This started hapening after I reinstalled matplotlib.

This is a numpy installation or version problem--notice that at the bottom of the traceback it is something from numpy that is not being found. Installation of numpy and mpl on OSX seems to be subject to all sorts of complications, and I don't use OSX, so I will have to leave this for someone else on the list.

Eric

···

  File "/Users/Kennel/Pythoncodes/coolingmodel.py", line 6, in <module>
    import matplotlib
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/__init__.py", line 129, in <module>
    from rcsetup import defaultParams, validate_backend, validate_toolbar
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/rcsetup.py", line 19, in <module>
    from matplotlib.colors import is_color_like
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/colors.py", line 54, in <module>
    import matplotlib.cbook as cbook
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/matplotlib/cbook.py", line 10, in <module>
    import numpy.ma as ma
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy/ma/__init__.py", line 47, in <module>
    import extras
  File "/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/site-packages/numpy/ma/extras.py", line 45, in <module>
    from numpy.lib.index_tricks import AxisConcatenator
ImportError: cannot import name AxisConcatenator

The first few lines of my codes are:

from math import *
import exceptions
import pmag
import matplotlib
matplotlib.use("TkAgg")
import numpy as np
import matplotlib.pyplot as plt

Thanks a lot for all your help.

Mitra

On Nov 1, 2009, at 11:32 PM, Eric Firing wrote:

R. Mitra wrote:

Hi Eric
from math import *
import matplotlib
matplotlib.use("TkAgg")
from pylab import *
This is very basic I know. The above are the modules I am using. Is plt a separate module? Thanks.

With your method above, you don't need the "plt." part. "from pylab import *" is discouraged, however, except for quick interactive use. For scripts, it is generally considered better practice to use

import matplotlib
matplotlib.use("tkagg")
import numpy as np
import matplotlib.pyplot as plt

pyplot is the plot-related part of the pylab namespace; or to put it another way, pylab is pyplot plus numpy.

See http://matplotlib.sourceforge.net/faq/usage_faq.html

Eric

RM
On Nov 1, 2009, at 7:26 PM, Eric Firing wrote:

R. Mitra wrote:

Hi
    I am having problems with contourf(). Suppose I have two 10X30 arrays X,Y and a corresponding Z value array. How do I make the upper left to be the origin? I cannot use contour (Z,origin='upper') because the axis values gets messed up.

It sounds like maybe you want to reverse the y-axis. Try something like plt.gca().invert_yaxis() after your call to contourf.

Eric