On Tuesday 16 Nov 2010 15:35:31 Benjamin Root wrote: > On Mon, Nov 15, 2010 at 4:14 AM, Guy Griffiths > > <guy.griffi...@reading.ac.uk>wrote: > > On Friday 12 Nov 2010 15:20:43 Ryan May wrote: > > > On Fri, Nov 12, 2010 at 8:40 AM, Benjamin Root <ben.r...@ou.edu> wrote: > > > > On Fri, Nov 12, 2010 at 5:11 AM, Guy Griffiths > > > > <guy.griffi...@reading.ac.uk> > > > > > > > > wrote: > > > >> Hi, > > > >> > > > >> I've been using matplotlib for a while for plotting scientific data, > > > > and > > > > > >> recently upgraded from version 0.99.1.1 to 1.0.0. Primarily I use > > > >> pcolor to > > > >> produce plots of concentration in 2D space. I use reasonably fine > > > >> meshes, and > > > >> in v0.99.1.1 the output looked great. > > > >> > > > >> In v1.0.0, all of my plots (using the same code) have faint > > > >> gridlines visible. > > > >> Since the mesh I am using is quite fine, this makes the plots look > > > >> terrible > > > >> (i.e. more gridlines than actual data). This seems to be controlled > > > > by > > > > > >> the > > > >> "edgecolors" keyword, but even when set to 'none' they are still > > > > there. > > > > > >> Is > > > >> > > > >> there any way to remove them completely without reverting back to > > > >> 0.99.1.1 (which I'd prefer not to do, since some of the API changes > > > > are > > > > > >> really useful > > > >> for creating very polished graphs suitable for publication)? > > > >> > > > >> imshow seems to have closer results to what I want (i.e. no > > > > gridlines), > > > > > >> but > > > >> with imshow, the axes denote the pixel position, and there is no > > > > option > > > > > >> to display on polar axes (which is essential). > > > >> > > > >> Any help would be much appreciated. > > > >> > > > >> Regards, > > > >> > > > >> Guy Griffiths > > > > > > > > Guy, I have noticed something similar a few months ago with pcolor, > > > > but > > > > I > > > > > > am not certain if it is the same problem as yours. First, which > > > > backend > > > > > > are you using? Second, are you seeing the grid lines in both the > > > > figure > > > > > > window and the saved output? Also, what format are you saving your > > > > output to? Lastly, which pcolor function are you using (pcolor(), > > > > pcolormesh(), pcolorfast())? > > > > > > > > If you could include a screenshot or the saved file, I could see if > > > > it > > > > is > > > > > > similar to my problem. > > > > > > Yeah, I had noticed a problem with pcolor too. You can see the problem > > > > > I've been seeing here: > > http://matplotlib.sourceforge.net/examples/pylab_examples/pcolor_demo.htm > > l > > > > > Calling pcolor with antialiased=False removes the lines, but that's > > > just a workaround, not a solution. I'm not really sure where to start > > > to track this down, so if anyone has a suggestion, I'm all ears. > > > > > > Ryan > > > > Hi, > > > > Thanks for the help. The problem I'm seeing is as Ryan describes (same > > effect > > as in the screenshot, but let me know if you still want me to provide an > > example), and appears in both the figure window and saved output (at > > least png > > and pdf). The backend I am using is Qt/Agg. I was using pcolor(), but > > it appears that pcolormesh() doesn't (always) have this problem. > > Setting antialiased=False removes some of the problems. In summary: > > > > pcolor(), antialiased=True - lines on screen, png, pdf > > pcolor(), antialiased=False - lines on pdf, fine on png/screen > > pcolormesh() - lines on pdf, fine on png/screen > > > > Regards, > > > > Guy > > Guy, > > I found my old bug report on this visual artifact. Oddly enough, the > problem for me was with pcolormesh, not with pcolor. There is a script > attached to the report that tests 4 combinations of function calls and > rasterized=True. Could you see how it turns out for you? > > Thanks, > Ben Root
Ben, I've run the script attached to the bug report. The results I got were as follows: PNG - Artifacts on both pcolor() plots, no artifacts on either pcolormesh() plot PDF - Artifacts on pcolor() and pcolormesh() with rasterized=False. Less obvious artifacts on pcolor() with rasterized=True. No artifacts on pcolormesh() with rasterized=True EPS - Artifacts on pcolor() with rasterized=True. All others fine SVG - Artifacts on pcolor() and pcolormesh() with rasterized=False. More obvious artifacts on pcolor() with rasterized=True. No artifacts on pcolormesh() with rasterized=True Hope this is helpful. Cheers, Guy ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 & L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today http://p.sf.net/sfu/msIE9-sfdev2dev _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
