That looks fine to me too, but if you plot that as one subplot in a 5x5 array of subplots or more, then you can see the shift I am talking about in the eps file. Example:
import matplotlib.pyplot as plt import numpy as np arr = np.zeros((11, 11), dtype="d") arr[3,3]=1 plt.figure(1) plt.subplot(10,10,1) im = plt.imshow(arr, interpolation="nearest", origin="lower") cont = plt.contour(arr, levels=[0.5]) plt.savefig("a.eps") Jae-Joon Lee wrote: > > I tried a simple array (see the code below) but cannot reproduce the > problem you reported. > > import matplotlib.pyplot as plt > import numpy as np > > arr = np.zeros((11, 11), dtype="d") > arr[3,3]=1 > im = plt.imshow(arr, interpolation="nearest", origin="lower") > cont = plt.contour(arr, levels=[0.5]) > plt.savefig("a.eps") > > Do you still see the shift with the above example code? > And what version of matplotlib are you using? > > If possible, please post a complete script with the data (use a > mock-up data if you want)? > Regards, > > -JJ > > > > On Fri, Jul 23, 2010 at 12:16 AM, Jenna Lemonias > <je...@astro.columbia.edu> wrote: >> No, I don't think the issue is a flip in the y-axis. I have a number of >> different examples of this, and many in which the contour is an ellipse >> so I >> can tell that the overall positioning is correct. It seems like >> something >> is going wrong only when I save the image... Thanks for the suggestion >> though! >> >> Jenna >> >> On Wed, Jul 21, 2010 at 3:40 PM, Jenna Lemonias >> <je...@astro.columbia.edu>wrote: >> >>> I am trying to save a matplotlib 2d array image with an overlaid contour >>> as >>> an eps file. The contour appears to be shifted with respect to the >>> image >>> underneath in the eps file, particularly when I zoom in on the image. >>> This >>> shift is not noticeable in the plot within matplotlib. >>> >>> I am using imshow to display the image. The contour is created by >>> plotting >>> a list of closely-spaced x,y coordinates. The attached file >>> matplotlib.png >>> is a screenshot of the (zoomed-in) image as displayed by matplotlib. >>> The >>> attached file epsfile.png is a screenshot of the (zoomed-in) eps file. >>> When >>> I save this image as an eps file, it is actually 1 of 20 subplots and >>> the >>> shift is noticeable in each subplot. >>> >>> Thanks in advance for your help! >>> >>> Jenna >>> >>> >> Just as a wild guess, could this actually be an issue with how imshow >> uses >> the upper-left corner for (0,0)? I have seen 1-pixel shifts before, but >> this shift is a little dramatic and I am left wondering if what we are >> really seeing is that the contour that is desired should actually be >> fliped >> in the y-axis? >> >> Maybe you could try another example where you try to draw a contour >> further >> away from the center of the image and see if it still goes in the spot >> you >> expect it to be? >> >> Ben Root >> >> ------------------------------------------------------------------------------ >> This SF.net email is sponsored by Sprint >> What will you do first with EVO, the first 4G phone? >> Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first >> _______________________________________________ >> Matplotlib-users mailing list >> Matplotlib-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/matplotlib-users >> >> > > ------------------------------------------------------------------------------ > The Palm PDK Hot Apps Program offers developers who use the > Plug-In Development Kit to bring their C/C++ apps to Palm for a share > of $1 Million in cash or HP Products. Visit us here for more details: > http://ad.doubleclick.net/clk;226879339;13503038;l? > http://clk.atdmt.com/CRS/go/247765532/direct/01/ > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > -- View this message in context: http://old.nabble.com/Saving-as-eps-file-shifts-image--tp29232680p29288310.html Sent from the matplotlib - users mailing list archive at Nabble.com. ------------------------------------------------------------------------------ The Palm PDK Hot Apps Program offers developers who use the Plug-In Development Kit to bring their C/C++ apps to Palm for a share of $1 Million in cash or HP Products. Visit us here for more details: http://p.sf.net/sfu/dev2dev-palm _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users