[Matplotlib-users] Why the V parameter in matplotlib.axes.Axes.contour must be increasing?

Jody Klymak jklymak at uvic.ca
Wed Aug 16 22:36:52 EDT 2017


I opened a pull request to change it, but we need to test a couple of 
things…

https://github.com/matplotlib/matplotlib/pull/9047

Cheers,  Jody

On 16 Aug 2017, at 19:06, Xi Shen wrote:

> Hi Jody,
>
> I confirm that giving V = [0] to contour function in matplotlib gives 
> me
> the same image as using V = [0 0] in MATLAB.
>
> Do you think it is a bug in matplotlib, or it is just a conscious 
> design
> decision? I do not have much knowledge of math behind this, so for me 
> it is
> just a restriction on parameter values.
>
>
> Thanks,
> David
>
>
> On Thu, Aug 17, 2017 at 12:48 AM Jody Klymak <jklymak at uvic.ca> wrote:
>
>> Hi David,
>>
>> I’ve definitely run into this, to my annoyance.
>>
>> Do you think you can open an issue on GitHub
>> <https://github.com/matplotlib/matplotlib/issues>? If you don’t 
>> want to,
>> I’m happy to do it.
>>
>> With respect to one contour at zero, its easier than Matlab:
>>
>> ax.contour(X, np.array([0.]))
>>
>> works for me…
>>
>> Cheers,
>>
>> On 16 Aug 2017, at 5:33, Xi Shen wrote:
>>
>> Hi,
>>
>> https://matplotlib.org/api/_as_gen/matplotlib.axes.Axes.contour.html 
>> says
>> the contour function accept a vector parameter V which must be in
>> increasing value. But the contour function in MATLAB does not have 
>> this
>> restriction.
>>
>> I understand the underlining implementation of these two functions 
>> could
>> be very different. I want to understand what is the purpose of this
>> restriction, and if it possible to create a contour image the same as
>> MATLAB does by using contour with V = [0 0]?
>>
>>
>> Regards,
>> David
>>
>> _______________________________________________
>> Matplotlib-users mailing list
>> Matplotlib-users at python.org
>> https://mail.python.org/mailman/listinfo/matplotlib-users
>>


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/matplotlib-users/attachments/20170816/282e72a6/attachment-0001.html>


More information about the Matplotlib-users mailing list