matplotlib-users Mailing List for matplotlib

Peter,

You’re welcome.

While I appreciate that you are trying to cut down on unnecessary emails (as per emailcharter.org - interesting read), it is appropriate to include the list in your responses, especially one indicating that a solution has been found, so that others on the list stop thinking about how they could help, and so that a person reading the archived list messages can feel confident that the suggestions were worthwhile. :-)  NNTR

-Sterling

On Feb 20, 2015, at 3:20PM, Peter Rowat <pe...@pe...> wrote:

> Thank you both for your help, my problem is solved. You both had similar suggestions, and now I have a slightly better understanding of matplotlib.
> 
> Peter
> Save our in-boxes! http://emailcharter.org 
> 
> 
> 
>> On Feb 20, 2015, at 12:48 AM, Fabrice Silva <si...@lm...> wrote:
>> 
>> Le jeudi 19 février 2015 à 23:10 -0800, Peter Rowat a écrit :
>>> I apologize for asking such a trivial question, but I’ve spent a long time trying to fix this:
>>> 
>>> I have a large 2D array that displays as an image, with a colorbar on the side.
>>> I also display 2 curves on top of the image. i.e. in same axes.
>>> The following code does it:
>>> 
>>>    fig,ax = plt.subplots()
>>>    cax = ax.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>>>        interpolation='nearest')
>>>    ax.set_title("Dummy title")
>>>    # Add colorbar
>>>    cbar = fig.colorbar(cax)
>>>    ax.set_ylabel('mV')
>>> 
>>>    ax.plot(emtrate, emrate, '.r')                  #curve 1
>>>    ax.plot(tt, rate*50 - 25.0, '-k', linewidth=3)  #curve 2
>>> 
>>>    plt.show()
>>> ========
>>> IN FACT,
>>> I want the curves in separate axes, below the image while the colorbar remains immediately to the right
>>> of the image.
>>> 
>>> I've tried many minor variations, for way over an hour..
>>> I've looked at demos, read about colorbar in several different parts of matplotlib docs...
>>> 
>>> Can someone help?? .... Either the colorbar is next to the last plot, or else I
>>> get an error.
>>> 
>>> Here is code that I've tried: It puts the colorbar in the wrong place, and in addition the image size
>>> is very small while the ax2 and ax3 curve plots are much wider. 
>>> I want the image and the second 2 plots the same width.
>>> 
>>> 
>>>    fig, (ax1, ax2,ax3) = plt.subplots(3,1)
>>>    cax = ax1.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>>>        interpolation='nearest')
>>>    ax1.set_title("Dummy title")
>>>    # Add colorbar
>>> #   cbar = fig.colorbar(cax)  # this places the colorbar next to the third subplot
>>>    plt.colorbar(cax)         # so does this
>> 
>> cax is not the Axes containing the image, but the image itself. It seems
>> that you want to "steal" some space to the first subplot so:
>> 
>>        fig, (ax1, ax2,ax3) = plt.subplots(3,1)
>>        im = ax1.imshow(bighistT, extent=myextent, cmap=cm.coolwarm,
>>        		aspect=myaspect, interpolation='nearest')
>>        ax1.set_title("Dummy title")
>>        cbar = fig.colorbar(im, ax=ax1)
>> 
>> or you can also create a new Axes between ax1 and ax2, and tell
>> colorbar() to put the Colorbar into (with the cax keyword argument)
>> 
>> See
>> http://matplotlib.org/api/figure_api.html#matplotlib.figure.Figure.colorbar
>> 
>> -- 
>> Fabrice
>> 
>> 
>> ------------------------------------------------------------------------------
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> 

*Call for Proposals*

*SciPy Latin América 2015*, the third annual Scientific Computing with
Python Conference, will be held this *May 20-22* in *Posadas, Misiones,
Argentina*.

SciPy is a community dedicated to the advancement of scientific computing
through open source Python software for mathematics, science, and
engineering. The annual SciPy Conferences allows participants from
academic, commercial, and governmental organizations to showcase their
latest projects, learn from skilled users and developers, and collaborate
on code development.

*Proposals are now being accepted for SciPy Latin América 2015*.

Presentation content can be at a novice, intermediate or advanced level.
Talks will run 30-40 min and hands-on tutorials will run 100-120 min. We
also receive proposal for posters. For more information about the different
types of proposal, see below the "*Different types of Communication*"
section.

*How to Submit?*

   1. Register for an account on http://conf.scipyla.org/user/register
   2. Submit your proposal at http://conf.scipyla.org/activity/propose

*Important Dates*

   - *April 6th*: Talks, poster, tutorial submission deadline.
   - *April 20th*: Notification Talks / Posters / Tutorial accepted.
   - *May 20th-22nd*: SciPy Latin América 2015.

*Different types of Communication*

*Talks*: These are the traditional talk sessions given during the main
conference days. They're mostly 30 minutes long with 5 min for questions.
If you think you have a topic but aren't sure how to propose it, contact
our program committee and we'll work with you. We'd love to help you come
up with a great proposal.

*Tutorials*: We are looking for tutorials that can grow this community at
any level. We aim for tutorials that will advance Scientific Python,
advance this community, and shape the future. They're are 100-120 minutes
long, but if you think you need more than one slot, you can split the
content and submit two self-contained proposals.

*Posters*: The poster session provides a more interactive, attendee-driven
presentation than the speaker-driven conference talks. Poster presentations
have fostered extensive discussions on the topics, with many that have gone
on much longer than the actual "session" called for. The idea is to present
your topic on poster board and as attendees mingle through the rows, they
find your topic, read through what you've written, then strike up a
discussion on it. It's as simple as that. You could be doing Q&A in the
first minute of the session with a group of 10 people.

*Lightning Talks*: Want to give a talk, but do not have enough material for
a full talk? These talks are, at max, 5 minute talks done in quick
succession in the main hall. No need to fill the whole slot, though!

-- 
*The SciPy LA 2015 Program **Committee*

Le jeudi 19 février 2015 à 23:10 -0800, Peter Rowat a écrit :
> I apologize for asking such a trivial question, but I’ve spent a long time trying to fix this:
> 
> I have a large 2D array that displays as an image, with a colorbar on the side.
> I also display 2 curves on top of the image. i.e. in same axes.
> The following code does it:
> 
>     fig,ax = plt.subplots()
>     cax = ax.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>         interpolation='nearest')
>     ax.set_title("Dummy title")
>     # Add colorbar
>     cbar = fig.colorbar(cax)
>     ax.set_ylabel('mV')
> 
>     ax.plot(emtrate, emrate, '.r')                  #curve 1
>     ax.plot(tt, rate*50 - 25.0, '-k', linewidth=3)  #curve 2
> 
>     plt.show()
> ========
> IN FACT,
> I want the curves in separate axes, below the image while the colorbar remains immediately to the right
> of the image.
> 
> I've tried many minor variations, for way over an hour..
> I've looked at demos, read about colorbar in several different parts of matplotlib docs...
> 
> Can someone help?? .... Either the colorbar is next to the last plot, or else I
> get an error.
> 
> Here is code that I've tried: It puts the colorbar in the wrong place, and in addition the image size
> is very small while the ax2 and ax3 curve plots are much wider. 
> I want the image and the second 2 plots the same width.
> 
> 
>     fig, (ax1, ax2,ax3) = plt.subplots(3,1)
>     cax = ax1.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>         interpolation='nearest')
>     ax1.set_title("Dummy title")
>     # Add colorbar
> #   cbar = fig.colorbar(cax)  # this places the colorbar next to the third subplot
>     plt.colorbar(cax)         # so does this

cax is not the Axes containing the image, but the image itself. It seems
that you want to "steal" some space to the first subplot so:

        fig, (ax1, ax2,ax3) = plt.subplots(3,1)
        im = ax1.imshow(bighistT, extent=myextent, cmap=cm.coolwarm,
        		aspect=myaspect, interpolation='nearest')
        ax1.set_title("Dummy title")
        cbar = fig.colorbar(im, ax=ax1)

or you can also create a new Axes between ax1 and ax2, and tell
colorbar() to put the Colorbar into (with the cax keyword argument)

See
http://matplotlib.org/api/figure_api.html#matplotlib.figure.Figure.colorbar

-- 
Fabrice

Peter,

I think that you want
cax = ax1.imshow(…)
cbar = fig.colorbar(cax,ax=ax1) # Where the ax keyword tells the colorbar which axes to steal space from. [1]

If you want the colorbar to be to the right of the first axes, and have the second and third axes line up with the first, then you need to create your own axes instance [2] {cbarax = fig.add_axes([…]) } for the colorbar and give that instance to the cax keyword of fig.colorbar (without an ax keyword). [1]

Also, I wouldn’t refer to the object returned by imshow as cax, as that is confusing when looking at the possible arguments of fig.colorbar.  I would call the image object im or something similar.  

-Sterling

[1] http://matplotlib.org/api/figure_api.html#matplotlib.figure.Figure.colorbar
[2] http://matplotlib.org/api/figure_api.html#matplotlib.figure.Figure.add_axes

On Feb 19, 2015, at 11:10PM, Peter Rowat <pe...@pe...> wrote:

> I apologize for asking such a trivial question, but I’ve spent a long time trying to fix this:
> 
> I have a large 2D array that displays as an image, with a colorbar on the side.
> I also display 2 curves on top of the image. i.e. in same axes.
> The following code does it:
> 
>     fig,ax = plt.subplots()
>     cax = ax.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>         interpolation='nearest')
>     ax.set_title("Dummy title")
>     # Add colorbar
>     cbar = fig.colorbar(cax)
>     ax.set_ylabel('mV')
> 
>     ax.plot(emtrate, emrate, '.r')                  #curve 1
>     ax.plot(tt, rate*50 - 25.0, '-k', linewidth=3)  #curve 2
> 
>     plt.show()
> ========
> IN FACT,
> I want the curves in separate axes, below the image while the colorbar remains immediately to the right
> of the image.
> 
> I've tried many minor variations, for way over an hour..
> I've looked at demos, read about colorbar in several different parts of matplotlib docs...
> 
> Can someone help?? .... Either the colorbar is next to the last plot, or else I
> get an error.
> 
> Here is code that I've tried: It puts the colorbar in the wrong place, and in addition the image size
> is very small while the ax2 and ax3 curve plots are much wider. 
> I want the image and the second 2 plots the same width.
> 
> 
>     fig, (ax1, ax2,ax3) = plt.subplots(3,1)
>     cax = ax1.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
>         interpolation='nearest')
>     ax1.set_title("Dummy title")
>     # Add colorbar
> #   cbar = fig.colorbar(cax)  # this places the colorbar next to the third subplot
>     plt.colorbar(cax)         # so does this
>     ax1.set_ylabel('mV')
>     ax2.plot(emtrate, emrate, '.r')
>     ax3.plot(tt, rate*50 - 25.0, '-k', linewidth=3)
> 
>     plt.show()
> Thanks for any help,
> 
> Peter
> Save our in-boxes! http://emailcharter.org 
> 
> 
> 
> ------------------------------------------------------------------------------
> Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
> from Actuate! Instantly Supercharge Your Business Reports and Dashboards
> with Interactivity, Sharing, Native Excel Exports, App Integration & more
> Get technology previously reserved for billion-dollar corporations, FREE
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> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

I apologize for asking such a trivial question, but I’ve spent a long time trying to fix this:

I have a large 2D array that displays as an image, with a colorbar on the side.
I also display 2 curves on top of the image. i.e. in same axes.
The following code does it:

    fig,ax = plt.subplots()
    cax = ax.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
        interpolation='nearest')
    ax.set_title("Dummy title")
    # Add colorbar
    cbar = fig.colorbar(cax)
    ax.set_ylabel('mV')

    ax.plot(emtrate, emrate, '.r')                  #curve 1
    ax.plot(tt, rate*50 - 25.0, '-k', linewidth=3)  #curve 2

    plt.show()
========
IN FACT,
I want the curves in separate axes, below the image while the colorbar remains immediately to the right
of the image.

I've tried many minor variations, for way over an hour..
I've looked at demos, read about colorbar in several different parts of matplotlib docs...

Can someone help?? .... Either the colorbar is next to the last plot, or else I
get an error.

Here is code that I've tried: It puts the colorbar in the wrong place, and in addition the image size
is very small while the ax2 and ax3 curve plots are much wider. 
I want the image and the second 2 plots the same width.


    fig, (ax1, ax2,ax3) = plt.subplots(3,1)
    cax = ax1.imshow(bighistT, extent=myextent, cmap = cm.coolwarm, aspect = myaspect,\
        interpolation='nearest')
    ax1.set_title("Dummy title")
    # Add colorbar
#   cbar = fig.colorbar(cax)  # this places the colorbar next to the third subplot
    plt.colorbar(cax)         # so does this
    ax1.set_ylabel('mV')
    ax2.plot(emtrate, emrate, '.r')
    ax3.plot(tt, rate*50 - 25.0, '-k', linewidth=3)

    plt.show()
Thanks for any help,

Peter
Save our in-boxes! http://emailcharter.org