matplotlib-users Mailing List for matplotlib

Warren Weckesser, on 2011-08-01 09:49,  wrote:
> There are a couple examples here:
>     http://stackoverflow.com/questions/5656798/python-matplotlib-is-there-a-way-to-make-a-discontinuous-axis

I was going to say: 

Damn those stackoverflow cool kids, reinventing the wheel when we
already have an example for this in git:
https://github.com/matplotlib/matplotlib/blob/master/examples/pylab_examples/broken_axis.py

but now I see that's exactly the example that's the top answer,
there, heh.

best,
-- 
Paul Ivanov
314 address only used for lists,  off-list direct email at:
http://pirsquared.org | GPG/PGP key id: 0x0F3E28F7 

Hi All,

Something I use a lot in Matlab is probing points from a plot, basically
clicking to select the nearest point and show a tooltip with the x and y
values. I didn't manage to reproduce this exactly with matplotlib, but I
found the code from the link below which is close enough to what I need:

http://stackoverflow.com/questions/4652439/is-there-a-matplotlib-equivalent-of-matlabs-datacursormode

Is there a better way, or something along those lines is the best option?

Thanks in advance,
Tudor

I am writing gtk2 application on python, I need to plot a chart in
separate window and i just use this code

    def matplot_print(self, print_values):
        """\brief print data by matplotlib and shw the figure
        \param print_values [(name - is a string, [(datetime, value)]
- is a list of data to plot)] - list of charts to plot
        """
        fig = plt.figure()
        ax = fig.add_subplot(111)
        names = map(lambda a: a[0], print_values)
        lines  = map(lambda chart: ax.plot_date(map(lambda chd:
chd[0], chart[1]),
                                                map(lambda chy:
chy[1], chart[1]), '-'), print_values)
        plt.figlegend(lines, names, 'upper left')

        majloc = AutoDateLocator()
        majform = AutoDateFormatter(majloc)
        ax.xaxis.set_major_locator(majloc)
        ax.xaxis.set_major_formatter(majform)
        ax.autoscale_view()
        ax.grid(True)
        fig.autofmt_xdate()
        fig.show()

The figure is showing and everything works before closing the window
of figure. It seems that figure call gtk.main_quit() when closing it's
window. How to override this behaviour ?

Hi,

Just a quick point of information that might saved time to some of you.
Installation of matplotlib is now pretty straightforward on Mac OS X 10.7 with HomeBrew.

Let's say you want to install the last version :
$ brew install pkg-config
$ git clone git://github.com/matplotlib/matplotlib.git
$ cd matplotlib/
$ python setup.py build
$ sudo python setup.py install

The dependencies of matplotlib (libpng, freetype, etc) are all present in /usr/x11/lib, however they are not found via the installation process because of the absence of pkg-config on Mac OS X. By installing it with HomeBrew, everythings falls in place.

Thanks to Telliot99 for finding that out.
You can read the original blog post at : http://telliott99.blogspot.com/2011/07/matplotlib-on-os-x-lion-revised.html

pkg-config could be installed from source or via macport, just make sure the search path is configured correctly to include (this what HomeBrew actually does) :
/usr/x11/lib/pkgconfig/

To get more information on HomeBrew, visit : https://github.com/mxcl/homebrew

Hy all,

I recently had a pretty hard time trying to figure out how to properly
autoscale a plot after removing a line (see attached script). Finally
I found at [1] that I have to explicitly refresh the axes dataLim
before autoscaling.

In [1] John Hunter says that computing the proper dataLim can be
complicated if there are several types of artists in the axes, like
polygons and collections an that "[it] would be useful to have an Axes
method like "auto_datalim" to for the datalim to readjust to all the
current data."

My question is whether such a function has been implemented. Besides
any suggestions about how to deal with this are welcome. I just need
to adjust to lines right now but this may change in the future.

Best regards

Goyo

[1] http://old.nabble.com/Removing-a-line-from-a-plot-td7249600.html

On Fri, Jul 29, 2011 at 4:51 PM, Mátyás János <mj...@gm...> wrote:

> Dear users,
>
> I would like to draw lines with fixed pixel thickness, for example 1,
> 2, or 3 pixels, which remains 1 pixel, even if I zoom in and out the
> graph in my interactive application. How can I do this with matplotlib?
>
> I tried to set linewidth to 1 on creating LineCollection, but this
> creates too thick lines. If I set it to 0.25 or 0.1, for example, then
> some lines on the screen are thin, but some line instances are
> simply missing (not visible), depending on the zoom.
>
>
> Thank you for your help,
>
> János
>
>
Janos,

This sounds like some bugs that may have been fixed at some point.  Which
version of matplotlib are you using, and which backend?

Ben Root

This is a bug in that matplotlib is not reading the preferred encoding 
correctly, because doing so has undesired side effects in some cases.  
An easy workaround is to add the following to the top of your script 
(before importing matplotlib):

import locale
locale.setlocale(locale.LC_ALL, '')

Note, you will also need to select a font that has Cyrillic characters.  
The default font shipped with matplotlib "Vera Sans" does not, but you 
can use its more-Unicode-complete sibling "DejaVu Sans" (installed on 
most Linux systems by default).

Interestingly, another use had a similar problem quite recently.  The 
following branch of matplotlib may also fix your problem:

https://github.com/mdboom/matplotlib/tree/locale_formatting

To test this, you would need to build it from source, and then set the 
rcParam "axes.formatter.use_locale" to True.

Cheers,
Mike

On 08/01/2011 12:23 AM, Alexey Uimanov wrote:
> Here the code
> #!/usr/bin/env python
>
> from pylab import figure, show
> from matplotlib.dates import AutoDateLocator, AutoDateFormatter,
> drange, DateFormatter
> import datetime
> import random
>
> dates = drange(datetime.datetime(2010, 1, 1), datetime.datetime(2010,
> 12,31), datetime.timedelta(days = 1))
> opens = map(lambda a: random.random(), dates)
>
> fig = figure()
> ax = fig.add_subplot(111)
> ax.plot_date(dates, opens, '-')
>
> majloc = AutoDateLocator()
> majform = AutoDateFormatter(majloc)
>
> ax.xaxis.set_major_locator(majloc)
> ax.xaxis.set_major_formatter(majform)
> ax.autoscale_view()
> ax.grid(True)
> fig.autofmt_xdate()
> show()
> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> It is just the same code as date_demo1.py from examples directory with
> some modifications
> My current locale is ru_RU.UTF-8 and i want plot the date ruller along
> X axis in format of my locale, with russian names of months.
> I can not do this because of this error when printing the chart
> Traceback (most recent call last):
>    File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_gtk.py",
> line 394, in expose_event
>      self._render_figure(self._pixmap, w, h)
>    File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_gtkagg.py",
> line 75, in _render_figure
>      FigureCanvasAgg.draw(self)
>    File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_agg.py",
> line 394, in draw
>      self.figure.draw(self.renderer)
>    File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
> 55, in draw_wrapper
>      draw(artist, renderer, *args, **kwargs)
>    File "/usr/lib/python2.7/site-packages/matplotlib/figure.py", line
> 798, in draw
>      func(*args)
>    File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
> 55, in draw_wrapper
>      draw(artist, renderer, *args, **kwargs)
>    File "/usr/lib/python2.7/site-packages/matplotlib/axes.py", line 1946, in draw
>      a.draw(renderer)
>    File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
> 55, in draw_wrapper
>      draw(artist, renderer, *args, **kwargs)
>    File "/usr/lib/python2.7/site-packages/matplotlib/axis.py", line 971, in draw
>      tick_tups = [ t for t in self.iter_ticks()]
>    File "/usr/lib/python2.7/site-packages/matplotlib/axis.py", line
> 907, in iter_ticks
>      majorLabels = [self.major.formatter(val, i) for i, val in
> enumerate(majorLocs)]
>    File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
> 486, in __call__
>      return self._formatter(x, pos)
>    File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
> 336, in __call__
>      return self.strftime(dt, self.fmt)
>    File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
> 362, in strftime
>      return cbook.unicode_safe(dt.strftime(fmt))
>    File "/usr/lib/python2.7/site-packages/matplotlib/cbook.py", line
> 41, in unicode_safe
>      else: return unicode(s, preferredencoding)
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xd0 in position
> 0: ordinal not in range(128)
> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> When lauching this with LANG=C everythig works but datetime prints in
> english locale.
> Version of matplotlib is 1.0.1
> What am i doing wrong ?
>
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-- 
Michael Droettboom
Science Software Branch
Space Telescope Science Institute
Baltimore, Maryland, USA

On Thu, Jul 28, 2011 at 5:41 AM, denoise <hub...@pa...> wrote:
>
> Hi there,
>
> i'd like to plot a data series with signal values over timestamps, what
> works perfectly. But if I want to display 2 series with different time
> domains, theres a gap in between.
> For example my first set of data is from time (x) 1-3 and the second from
> 7-8. If I send the mixed array to the plot, I will receive something like
> that:
>
> y|    x x x         x x x
> x| 0 1 2 3 4 5 6 7 8 9 10 11
>
> But if there is considerably more time between the to data sets, it soon
> will look confusing.
> What i need is a graph over this:
>
> y| x x x   x x x
> x| 1 2 3  7 8 9
>
> Of course I could do this with 2 subplots, but i want to scroll over a whole
> set of data.
> Is it possible wih matplotlib, or is there a workaround?


There are a couple examples here:
    http://stackoverflow.com/questions/5656798/python-matplotlib-is-there-a-way-to-make-a-discontinuous-axis


Warren



>
> Thanks!
> Hubert
>
> --
> View this message in context: http://old.nabble.com/plot-with-discontinuous-x-axis-tp32155499p32155499.html
> Sent from the matplotlib - users mailing list archive at Nabble.com.
>
>
> ------------------------------------------------------------------------------
> Got Input?   Slashdot Needs You.
> Take our quick survey online.  Come on, we don't ask for help often.
> Plus, you'll get a chance to win $100 to spend on ThinkGeek.
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> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
>

Here the code
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
#!/usr/bin/env python

from pylab import figure, show
from matplotlib.dates import AutoDateLocator, AutoDateFormatter,
drange, DateFormatter
import datetime
import random

dates = drange(datetime.datetime(2010, 1, 1), datetime.datetime(2010,
12,31), datetime.timedelta(days = 1))
opens = map(lambda a: random.random(), dates)

fig = figure()
ax = fig.add_subplot(111)
ax.plot_date(dates, opens, '-')

majloc = AutoDateLocator()
majform = AutoDateFormatter(majloc)

ax.xaxis.set_major_locator(majloc)
ax.xaxis.set_major_formatter(majform)
ax.autoscale_view()
ax.grid(True)
fig.autofmt_xdate()
show()
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
It is just the same code as date_demo1.py from examples directory with
some modifications
My current locale is ru_RU.UTF-8 and i want plot the date ruller along
X axis in format of my locale, with russian names of months.
I can not do this because of this error when printing the chart
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_gtk.py",
line 394, in expose_event
    self._render_figure(self._pixmap, w, h)
  File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_gtkagg.py",
line 75, in _render_figure
    FigureCanvasAgg.draw(self)
  File "/usr/lib/python2.7/site-packages/matplotlib/backends/backend_agg.py",
line 394, in draw
    self.figure.draw(self.renderer)
  File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/matplotlib/figure.py", line
798, in draw
    func(*args)
  File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/matplotlib/axes.py", line 1946, in draw
    a.draw(renderer)
  File "/usr/lib/python2.7/site-packages/matplotlib/artist.py", line
55, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/matplotlib/axis.py", line 971, in draw
    tick_tups = [ t for t in self.iter_ticks()]
  File "/usr/lib/python2.7/site-packages/matplotlib/axis.py", line
907, in iter_ticks
    majorLabels = [self.major.formatter(val, i) for i, val in
enumerate(majorLocs)]
  File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
486, in __call__
    return self._formatter(x, pos)
  File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
336, in __call__
    return self.strftime(dt, self.fmt)
  File "/usr/lib/python2.7/site-packages/matplotlib/dates.py", line
362, in strftime
    return cbook.unicode_safe(dt.strftime(fmt))
  File "/usr/lib/python2.7/site-packages/matplotlib/cbook.py", line
41, in unicode_safe
    else: return unicode(s, preferredencoding)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xd0 in position
0: ordinal not in range(128)
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
When lauching this with LANG=C everythig works but datetime prints in
english locale.
Version of matplotlib is 1.0.1
What am i doing wrong ?