matplotlib-users Mailing List for matplotlib

On Nov 23, 2011, at 4:09 PM, C M wrote:
>
>
> On Tue, Nov 22, 2011 at 3:09 PM, Nicolas Rougier 
> <Nic...@in...> wrote:
>
> Is that what you want ?
>
> No ticks, no labels:
>
> import matplotlib.pyplot as plt
> plt.plot(np.arange(10), np.arange(10))
> plt.ylim(0,10)
> plt.yticks(np.linspace(3,10,8))
> plt.show()
>
> Thanks. That works in your example, but in my actual code, it 
> seems to override my custom formatter, and therefore messes up the 
> axis formatting, which isn't going to work.
>
> Maybe I can integrate it into the formatter somehow. If anyone has 
> related tips, please let me know.
I don't know if this will work for you, but in your situation I would 
probably just make another axis for the data with no y value. Like, a 
short squat axis directly below the main axis.
-Jeff

The original message with attachment didn't go thru...
Begin forwarded message:
*From:* Arlindo da Silva <da...@al...>
*To:* matplotlib-users <mat...@li...>
*Subject:* *Bug or feature: bbox of maps*
Hi,
 (A similar issue was reported back in 7/4/11 without a definite solution,
so I am reposting with some additional diagnostics. ) Up to Matplotlib 0.99
(EPD 6.3) the code snippet below produced a plot with an aligned colorbar
as in the attached "correct.png" plot:
 fig = plt.figure()
 ax = fig.add_axes(...)
 m = Basemap(..., ax=ax, ...)
 im = m.imshow(...)
 # show()
 # setup colorbar axes and draw colorbar
 bbox = ax.get_position()
 l,b,w,h = bbox.bounds
 cax = fig.add_axes([l+w+0.05, b, 0.05, h],frameon=False)
 fig.colorbar(im, cax=cax)
Starting with Matplotlib 1.0.0 this no longer works. The ax.get_position()
no longer returns the bounding box of the plot but the bbox of the window,
see the attached "wrong.png" attached. Some odd behavior:
1) I can get the code above to work correctly under MPL 1.0 if I uncomment
the show() line above. (This is not an acceptable solution because show()
blocks if not in interactive mode).
2) Under ipython, if after plotting I print gca().get_position().bounds I
get the correct bounding box, even when I just got the wrong colorbar
positioning.
3) If I run the code above twice in a row (without creating a new fig), the
second time around the correct bounding box is returned.
 Can someone explain to me what is going on? Is this one of those arcane
features of matplotlib transform caching? It appears that show() is
flushing some type of buffer. Is there any way of accomplishing this
without actually calling show()?
 Thank you,
 Arlindo
-- 
Arlindo da Silva
da...@al...
<correct.png>
<wrong.png>

On Tue, Nov 22, 2011 at 3:09 PM, Nicolas Rougier
<Nic...@in...>wrote:
>
> Is that what you want ?
>
> No ticks, no labels:
>
> import matplotlib.pyplot as plt
> plt.plot(np.arange(10), np.arange(10))
> plt.ylim(0,10)
> plt.yticks(np.linspace(3,10,8))
> plt.show()
>
Thanks. That works in your example, but in my actual code, it seems to
override my custom formatter, and therefore messes up the axis formatting,
which isn't going to work.
Maybe I can integrate it into the formatter somehow. If anyone has related
tips, please let me know.
Che

On Wednesday, November 23, 2011, Bala subramanian <bal...@gm...>
wrote:
> Hello,
> I am trying to make a wireframe plot with the x,y,z values in my data
(attached file). I get the following error which i dnt understand. Kindly
write me what is going wrong.
>
> Traceback (most recent call last):
> File "test.py", line 14, in <module>
> ax.plot_wireframe(d1,d2,d3)
> File "/usr/lib/pymodules/python2.7/mpl_toolkits/mplot3d/axes3d.py",
line 687, in plot_wireframe
> rows, cols = Z.shape
> ValueError: need more than 1 value to unpack
>
> I used is similar code as in the gallery.
>
> #!/usr/bin/env python
> import numpy as np
> from mpl_toolkits.mplot3d import Axes3D
> import matplotlib.pyplot as plt
>
> d1=np.loadtxt('test.dat',usecols=(0,))
> d2=np.loadtxt('test.dat',usecols=(1,))
> d3=np.loadtxt('test.dat',usecols=(2,))
>
> fig=plt.figure()
> ax = Axes3D(fig)
>
> ax.plot_wireframe(d1,d2,d3)
>
> Thanks,
> Bala
>
>
The data needs to be 2d. I think the x and y can be 1d, so long as they
can be broadcasted together to the same shape as Z.
Ben Root

Dear mailinglist readers,
I have a problem by accessing the content
http://matplotlib.sourceforge.net/examples/pylab_examples/demo_tight_layout_00.html
whereas other contents, like for example
http://matplotlib.sourceforge.net/examples/pylab_examples/demo_ribbon_box.html
are well accessible. Is there a reason, why this content is not available?
I would be glad, if you might help.
Best regards,
Sven Ahrens
The error message:
An error has been encountered in accessing this page.
1. *Server:* matplotlib.sourceforge.net
2. *URL path:* /examples/pylab_examples/demo_tight_layout_00.html
3. *Error notes:* NONE
4. *Error type:* 404
5. *Request method:* GET
6. *Request query string:* NONE
7. *Time:* 2011年11月23日 12:45:59 UTC (1322052359)

Dear MatPlotLib users,
 
I am having trouble with the performance of matplotlib.
For data analysis, I want to be able to place multiple graphs on screen,
with multiple lines, each consisting of 16000 data points.
 
I have benchmarked my solution, but it did not perform too well.
For example: 6 graphs with 6 lines each, takes 12.5 seconds.
This graph indicates my benchmark:
http://img59.imageshack.us/img59/7613/graphpython.gif
In comparison, matlab takes only 2.48 seconds for drawing those.
 
I also noticed that memory usage during the benchmark rises to too high levels.
I have, during a different experiment, plotted 36 graphs with 1 line.
This is about 9MB of total (x,y) data alltogether, but execution of the benchmark 
spikes 1GB of memory usage.
 
My question: 
- Is this performance of matplotlib to be expected?
- Can my code (see below) be improved in any way?
 
Thank you very much in advance,
 
Mike
 
 
================================
The code I use for the benchmark
================================
for nr_of_graphs in range (1,7):
 for nr_of_lines in range(1,7):
 root = Tk.Tk()
 #nr_of_lines = int(argv[0])
 #nr_of_graphs = int(argv[1])
 m = myLinMultiPlot()
 m.drawxy("test {0}L on {1}G".format(nr_of_lines, nr_of_graphs), nr_of_graphs, nr_of_lines)
 root.mainloop()
================================
The code that plots the actual lines
================================
class myLinMultiPlot(Tk.Toplevel):
 def drawxy(self, test_name, plots, lines):
 pointsize = 16000
 figure = Figure(figsize=(2,1), dpi=100)
 storage = []
 axes_arr = []
 for p in range(0,plots):
 for li in range(0,lines):
 shift = li * 100
 axes = figure.add_subplot(plots,1,1 + p)
 axes_arr.append(axes)
 xarr = xrange(0,16000)
 yarr = []
 for x in xarr:
 yarr.append(math.sqrt(x + shift))
 strg = [xarr,yarr]
 storage.append(strg)
 startdraw = timeit.default_timer()
 for a in axes_arr:
 for l in storage:
 a.plot(l[0],l[1])
 canvas = FigureCanvasTkAgg(figure, master = self)
 canvas._tkcanvas.pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)
 canvas.show()
 canvas.blit()
 //This is the time depicted in my benchmark!
 durationdraw = timeit.default_timer() - startdraw 		 	 		 		 	 		 

On 11/23/11 9:49 AM, Chao YUE wrote:
> Dear all,
>
> I am using matplotlib 0.99.3 (I think it's the default version when I use sudo
> apt-get install under ubuntu 11.04), but I don't have matplotlib.animation
> module. I think I need to reinstall it?
The animation module was added in matplotlib 1.1.0. You will have to install 
that version instead.
-- 
Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
 -- Umberto Eco

Dear MatPlotLib users,
 
I am having trouble with the performance of matplotlib.
For data analysis, I want to be able to place multiple graphs on screen,
with multiple lines, each consisting of 16000 data points.
 
I have benchmarked my solution, but it did not perform too well.
For example: 6 graphs with 6 lines each, takes 12.5 seconds.
This graph indicates my benchmark:
http://img59.imageshack.us/img59/7613/graphpython.gif
 
I also noticed that memory usage during the benchmark rises to too high levels.
I have, during a different experiment, plotted 36 graphs with 1 line.
This is about 9MB of total (x,y) data alltogether, but execution of the benchmark 
spikes 1GB of memory usage.
 
My question: 
- Is this performance of matplotlib to be expected?
- Can it be improved in any way?
 
Thank you very much in advance,
 
Anne
 
================================
The code I use for the benchmark
================================
for nr_of_graphs in range (1,7):
 for nr_of_lines in range(1,7):
 root = Tk.Tk()
 #nr_of_lines = int(argv[0])
 #nr_of_graphs = int(argv[1])
 m = myLinMultiPlot()
 m.drawxy("test {0}L on {1}G".format(nr_of_lines, nr_of_graphs), nr_of_graphs, nr_of_lines)
 root.mainloop()
================================
The code that plots the actual lines
================================
class myLinMultiPlot(Tk.Toplevel):
 def drawxy(self, test_name, plots, lines):
 pointsize = 16000
 figure = Figure(figsize=(2,1), dpi=100)
 storage = []
 axes_arr = []
 for p in range(0,plots):
 for li in range(0,lines):
 shift = li * 100
 axes = figure.add_subplot(plots,1,1 + p)
 axes_arr.append(axes)
 xarr = xrange(0,16000)
 yarr = []
 for x in xarr:
 yarr.append(math.sqrt(x + shift))
 strg = [xarr,yarr]
 storage.append(strg)
 startdraw = timeit.default_timer()
 for a in axes_arr:
 for l in storage:
 a.plot(l[0],l[1])
 canvas = FigureCanvasTkAgg(figure, master = self)
 canvas._tkcanvas.pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)
 canvas.show()
 canvas.blit()
 //This is the time depicted in my benchmark!
 durationdraw = timeit.default_timer() - startdraw 		 	 		 

Dear all,
I am using matplotlib 0.99.3 (I think it's the default version when I use
sudo apt-get install under ubuntu 11.04), but I don't have
matplotlib.animation module. I think I need to reinstall it?
thanks,
chao
-- 
***********************************************************************************
Chao YUE
Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL)
UMR 1572 CEA-CNRS-UVSQ
Batiment 712 - Pe 119
91191 GIF Sur YVETTE Cedex
Tel: (33) 01 69 08 29 02; Fax:01.69.08.77.16
************************************************************************************