Re: [Matplotlib-users] Problem with plotting fast spiking data

[John H. <jd...@gm...>]

On Thu, Feb 18, 2010 at 4:19 PM, Jakub Nowacki
<j.s...@go...> wrote:
> Hi,
>
> I work with neural models and I have problem with plotting fast spiking data. The spikes on the plot appear to have different hight which changes when I for example resize the plot window. The same problem is with saving data into files, especially in vector formats. I found the information about changing the join style, it helps a bit (rounded is the best) but doesn't solve the problem. For raster formats the workaround is to save the data in higher resolution, using DPI option. Below I included links to examples.
>
> Normal example (100 DPI):
> https://docs.google.com/leaf?id=0B3NZY3443E1VY2JjNTc3MjAtZDI5NC00OThjLTgwY2EtNTVhMDVkZWQ2YzIw&hl=en
>
> Example 300 DPI:
> https://docs.google.com/leaf?id=0B3NZY3443E1VNDdkMzUzNzAtMjdmNC00NjFmLTliMzMtODE5MzExMmNjNjQz&hl=en
>
> The problem is vector files (I'm especially interested in EPS) ignore DPI option. I've experimented with different backends and the problem is persistent on GUI and 'file-writting' back ends. I also tested it on Linux and Mac, and the outcome does't change. Creating larger figures sometimes helps a bit but not always solve the problem.
>
> Just to mention that plotting this kind of data is possible 'out of the box'  in Matlab or XPPAut (which is not the most fancy plotting tool) I get a proper outcome. Maybe there should be a option to plot raw data in some sense, or join style function that deals with such a plots in a proper fashion.
>
> If you need some additional information do not hesitate to ask. Thanks for the help in advance.


This is a known bug in the latest release of mpl that is fixed in svn.
 We do need to get a new release out soon.

It is easy to fix by uncomennting the

  path.simplify : False

line in your matplotlibrc file (the default is True).  Note that
path.simplify does work in the svn release of matplotlib -- it is
designed to reduce paths but be imperceptible to the eye at the
resolution plotted, but due to a bug in the released version it can
result in improper simplifications.


See  http://matplotlib.sourceforge.net/users/customizing.html for
information on how to change your matplotlibrc settings.

JDH