hello ppl,
hey i hav 3 .dat files... one has 1 column of x coords, another has 1 column
of the same number of y coords and the last .dat file has the same number of
corresponding values of a property[temperature] at those points in 1
column.... i was wondering how i cud make a contour of this data with the
last .dat file being the z-values... i hav written the following code(
saf2.py)[mind u ppl am a newbie @ python+matplotlib]...
from pylab import *
x = load('xcord2.dat')
y = load('ycord2.dat')
X, Y = meshgrid(x, y)
Z = load('output1im.dat')
contour(X,Y,Z)
show()
the following errors crop up:
Traceback (most recent call last):
File "F:\Python25\saf2.py", line 9, in <module>
contour(X,Y,Z)
File "F:\Python25\Lib\site-packages\matplotlib\pylab.py", line 1776, in
contour
ret = gca().contour(*args, **kwargs)
File "F:\Python25\Lib\site-packages\matplotlib\axes.py", line 4674, in
contour
return ContourSet(self, *args, **kwargs)
File "F:\Python25\Lib\site-packages\matplotlib\contour.py", line 429, in
__init__
x, y, z = self._contour_args(*args) # also sets self.levels,
File "F:\Python25\Lib\site-packages\matplotlib\contour.py", line 601, in
_contour_args
x,y,z = self._check_xyz(args[:3])
File "F:\Python25\Lib\site-packages\matplotlib\contour.py", line 577, in
_check_xyz
raise TypeError("Input z must be a 2D array.")
TypeError: Input z must be a 2D array.
wat errors am i making?
My understanding is the "contour" method only handles plots of functions, e.g. f(x,y) = z, and not discrete points. I tried looking into this weeks ago, and couldn't find a way to handle discrete points. I'd love to be able to do Kriging or Inverse Distance Weighting contour lines on XY points I have of pollution concentrations at various monitors...
Michael Newman wrote: > My understanding is the "contour" method only handles plots of > functions, e.g. f(x,y) = z, and not discrete points. I tried looking > into this weeks ago, and couldn't find a way to handle discrete points. > > I'd love to be able to do Kriging or Inverse Distance Weighting contour > lines on XY points I have of pollution concentrations at various monitors... > > Michael: There are three different methods for doing this described at http://www.scipy.org/Cookbook/Matplotlib/Gridding_irregularly_spaced_data -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449 325 Broadway Boulder, CO, USA 80305-3328
On 7/3/07, Jeff Whitaker <js...@fa...> wrote: > > Michael Newman wrote: > > My understanding is the "contour" method only handles plots of > > functions, e.g. f(x,y) = z, and not discrete points. I tried looking > > into this weeks ago, and couldn't find a way to handle discrete points. > > > > I'd love to be able to do Kriging or Inverse Distance Weighting contour > > lines on XY points I have of pollution concentrations at various > monitors... > > > > > Michael: There are three different methods for doing this described at > > http://www.scipy.org/Cookbook/Matplotlib/Gridding_irregularly_spaced_data > > -Jeff > > -- > Jeffrey S. Whitaker Phone : (303)497-6313 > NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449 > 325 Broadway Boulder, CO, USA 80305-3328 > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > _______________________________________________ > Matplotlib-users mailing list > Mat...@li... > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > hey guys... i got it... u can use contour(x,y,z)... as in x=load(' urfile1.dat'), y=load('urfile2.dat), z=load('urfile3.dat').... and then type out the above.... for details about the parameters x,y,z see... . http://www.scilab.org/product/man-eng/graphics/contour.htm .... so matplotlib CAN plot a contour from discrete points!!!.... ive tried it and it works...
Viraj Vajratkar wrote: > > > On 7/3/07, *Jeff Whitaker* <js...@fa... > <mailto:js...@fa...>> wrote: > > Michael Newman wrote: > > My understanding is the "contour" method only handles plots of > > functions, e.g. f(x,y) = z, and not discrete points. I tried looking > > into this weeks ago, and couldn't find a way to handle discrete > points. > > > > I'd love to be able to do Kriging or Inverse Distance Weighting > contour > > lines on XY points I have of pollution concentrations at various > monitors... > > > > > Michael: There are three different methods for doing this > described at > > http://www.scipy.org/Cookbook/Matplotlib/Gridding_irregularly_spaced_data > > -Jeff > > -- > Jeffrey S. Whitaker Phone : (303)497-6313 > NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449 > 325 Broadway Boulder, CO, USA 80305-3328 > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by DB2 Express > Download DB2 Express C - the FREE version of DB2 express and take > control of your XML. No limits. Just data. Click to get it now. > http://sourceforge.net/powerbar/db2/ > <http://sourceforge.net/powerbar/db2/> > _______________________________________________ > Matplotlib-users mailing list > Mat...@li... > <mailto:Mat...@li...> > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > hey guys... i got it... u can use contour(x,y,z)... as in > x=load('urfile1.dat'), y=load('urfile2.dat), z=load('urfile3.dat > ').... and then type out the above.... for details about the > parameters x,y,z see... . > http://www.scilab.org/product/man-eng/graphics/contour.htm .... so > matplotlib CAN plot a contour from discrete points!!!.... ive tried it > and it works... Viraj: That only works because x and y describe a rectangular grid. If x and y described irregularly spaced points, you would need to grid the data first using one of the methods described on that Cookbook page. -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449 325 Broadway Boulder, CO, USA 80305-3328