Re: [PyX-user] Drawing confidence bands around datapoints

[Michael S. <m-s...@us...>]

Hello Néstor,

On 28/08/13, Néstor Espinoza wrote:
>  I'm trying to draw confidence bands around some model data-points that I
> have and I think the tutorials that I've read so far that paint areas below
> curves are not what I'm looking for (e.g.,
> http://pyx.sourceforge.net/gallery/graphs/integral.html), because in order
> to paint areas between curves with those methods (i.e., by the method
> suggested in this same mailist here:
> http://osdir.com/ml/python.pyx.users/2008-07/msg00002.html), the trick is
> to paint white below the second curve.

I am not quite sure to understand what you want to do. If it is just
to visualize the confidence of the data, you could use simple error
bars (http://pyx.sourceforge.net/examples/graphstyles/errorbar.html).
I you want it more fancy with a shaded area, the principle is the same
as in the integral example: You take out the paths from the graph, and
those can be manipulated (glued together, split, ...). If this latter
step makes problems, have a look at the joint example.

>  Basically in my code I have three vectors, model, model_down and model_up.
> The idea is to plot the confidence bands between the curves model_down and
> model_up (which represent my confidence bads) and plot model as datapoints
> on top: do you have any idea on how to do this?

Best,
  Michael