preventing scaling view after updating plot

Community matplotlib-users
1

(mpl 0.98.5 OO embedded in wx)

Hi, I'm trying to highlight a picked datapoint, such as is shown in
this thread:

http://www.mail-archive.com/matplotlib-users@lists.sourceforge.net/msg05580.html

As John suggested there, I get the index of the picked point, and then
plot a marker on that point. I am using the OO mpl form, so then
I call, to draw this new point on the canvas:

self.canvas.draw()
(self.canvas is a figure.canvas object).

But when I do this it *rescales the plot*, which I don't want. In this thread:

http://www.nabble.com/Re%3A-Plotting-single-marker-point-at-zoomed-level-p17511209.html

I found someone mentioning this concern. He said:

Thanks for that, the canvas.draw() function redraws the graph.
I had to add the "autoscale_on=False" to the add_subplot()
to stop the graph from autoscaling.

I tried this, and it did stop autoscaling--but I do want y autoscaling.
What I want is y autoscaling but not y autoscaling (just setting xlims).
I tried adding either of these lines right before or right after when I plotted
the highlighted point:

self.subplot.set_autoscale_on(False)
self.subplot.autoscale_view(tight=False, scalex=False, scaley=True)

and it didn't help--the plot rescaled, both x and y.

Any ideas what I'm doing wrong?

Thanks,
Che

2

I tried this, and it did stop autoscaling--but I do want y autoscaling.
What I want is y autoscaling but not y autoscaling (just setting xlims).
I tried adding either of these lines right before or right after when I plotted
the highlighted point:

Just to be clearer: What I want is the plot to stay precisely the same
when I add the highlighted point. But now I have either of two undesired
alternatives:

1) I do add_subplot(111,autoscale_on=False) when I create the
subplot and none of my plots have the y scaled (but I want them scaled).

2) I do add_subplot(111) and when I add a highlighted datapoint it
autoscales my plot (but I don't want that).

Thanks,
Che

3

If you upgrade to SVN head, it supports what you want. You can use:

add_subplot(111, autoscalex_on=False)

I don’t think this particular feature has made it into a release yet.

Ryan

···

On Thu, Apr 9, 2009 at 1:04 AM, C M <cmpython@…287…> wrote:

I tried this, and it did stop autoscaling–but I do want y autoscaling.

What I want is y autoscaling but not y autoscaling (just setting xlims).

I tried adding either of these lines right before or right after when I plotted

the highlighted point:

Just to be clearer: What I want is the plot to stay precisely the same

when I add the highlighted point. But now I have either of two undesired

alternatives:

  1. I do add_subplot(111,autoscale_on=False) when I create the

subplot and none of my plots have the y scaled (but I want them scaled).

  1. I do add_subplot(111) and when I add a highlighted datapoint it

autoscales my plot (but I don’t want that).

–
Ryan May
Graduate Research Assistant
School of Meteorology
University of Oklahoma

4

Wow, thanks Ryan. This is the beauty of an email list. I'll try to
get it from SVN or back-burner this issue until the next release.

Che

···

On Thu, Apr 9, 2009 at 9:25 AM, Ryan May <rmay31@...287...> wrote:

On Thu, Apr 9, 2009 at 1:04 AM, C M <cmpython@...287...> wrote:

>
> I tried this, and it did stop autoscaling--but I do want y autoscaling.
> What I want is y autoscaling but not y autoscaling (just setting xlims).
> I tried adding either of these lines right before or right after when I
> plotted
> the highlighted point:

Just to be clearer: What I want is the plot to stay precisely the same
when I add the highlighted point. But now I have either of two undesired
alternatives:

1) I do add_subplot(111,autoscale_on=False) when I create the
subplot and none of my plots have the y scaled (but I want them scaled).

2) I do add_subplot(111) and when I add a highlighted datapoint it
autoscales my plot (but I don't want that).

If you upgrade to SVN head, it supports what you want. You can use:

add_subplot(111, autoscalex_on=False)

I don't think this particular feature has made it into a release yet.

Ryan
--
Ryan May
Graduate Research Assistant
School of Meteorology
University of Oklahoma