[matplotlib-devel] Exception for the colorbar of a imshow of zeroes

2010-05-21 Thread João Luís Silva
Hi, Using the SVN version the following example fails with: File /usr/local/lib/python2.6/dist-packages/matplotlib/colors.py, line 815, in inverse raise ValueError(Inversion requires valid vmax vmin) ValueError: Inversion requires valid vmax vmin This was introduced in svn revision

Re: [matplotlib-devel] Bug rasterized image in pcolor and pcolormesh

2010-05-21 Thread Benjamin Root
I have been doing some testing with pcolor() and pcolormesh() with regards to rasterization. I can not see a displacement when choosing between different file types or with setting rasterized to be True or False. What I have noticed is a half grid-space displacement between pcolor() and

Re: [matplotlib-devel] Bug rasterized image in pcolor and pcolormesh

2010-05-21 Thread Markus Haider
Hi, Thank you for your reply. I have been doing some testing with pcolor() and pcolormesh() with regards to rasterization. I can not see a displacement when choosing between different file types or with setting rasterized to be True or False. What I have noticed is a half grid-space

Re: [matplotlib-devel] Bug rasterized image in pcolor and pcolormesh

2010-05-21 Thread Benjamin Root
Markus, Looking again at your image, I realized that you are probably using real data, not simulated data, therefore you can't easily use a higher grid resolution. So, I created a test script to examine this. I have found that there is definitely a difference between filetypes. In my test

Re: [matplotlib-devel] Bug rasterized image in pcolor and pcolormesh

2010-05-21 Thread Jae-Joon Lee
If possible, can you try the latest svn version and see if it makes any difference? Also, see if increasing the dpi helps, i.e., savefig(..., dpi=150) Given the nature of the rasterization, I'm not sure if we can completely avoid the white gap for low dpi settings. But the displacement issue you

Re: [matplotlib-devel] Bug rasterized image in pcolor and pcolormesh

2010-05-21 Thread Benjamin Root
Hello, Attached is a test script to produce low and high resolution (data-wise) images in multiple formats. You can change the dpi in the script, however, I have not noticed any significant difference. It also appears that the data resolution doesn't impact the size of the artifact as much as I

Re: [matplotlib-devel] Exception for the colorbar of a imshow of zeroes

2010-05-21 Thread Eric Firing
On 05/21/2010 03:55 AM, João Luís Silva wrote: Hi, Using the SVN version the following example fails with: File /usr/local/lib/python2.6/dist-packages/matplotlib/colors.py, line 815, in inverse raise ValueError(Inversion requires valid vmax vmin) ValueError: Inversion requires valid

Re: [matplotlib-devel] basemap domain changes on pyplot call

2010-05-21 Thread Benjamin Root
I did some more digging and I think I have a hypothesis for what is happening. There is only one main difference between a call to .drawstates() and .readshapefiles() with respect to loading and plotting data. .drawstates() loads *only* the line segments that coincide with the defined map