matplotlib-users Mailing List for matplotlib (Page 8)

I've also done some additional testing to see if I could figure out what
was going on, and it turns out that it's not just a problem with eps files.
This problem also occurs in the other vector graphics formats,
ps/eps/pdf/svg. In all cases the entire image is actually contained within
the file, it's just shifted and clipped. Sometimes it's shifted so much
that none of it is within the axes window and thus the entire image gets
clipped and it appears not to be there at all.

I also discovered that the time axis isn't actually a factor.

I've also noticed that using interpolation seems to make a difference. When
I use the default interpolation the plots *seem* to come out fine, although
some of my other data do look a little bit shifted, but that could be some
other effect.

Another weird thing that I've noticed is that different viewers interpret
this shifting in different ways. For example, the pdfs all look fine when I
view them in Okular, but are shifted in xpdf. (At some point I submitted a
second email to the list re: this problem that had screenshots attached. I
don't know if it ever made it through however.)

I'll submit the but report on the git tracker.

Round-off error could make sense.

--Chad

Here's my most recent set of test code:

import matplotlib.pyplot as plt
from matplotlib.colors import LogNorm

imgData = [[1.0/(x) + 1.0/(y) for x in range(1,100)] for y in range(1,100)]

tMin=734717.945208
tMax=734717.946366

# Case 0: Works
Case0={"id":0,
       "interp":None,
       "extents":(tMin,tMax,1,100)}

# Case 1: Works
Case1={"id":1,
       "interp":"none",
       "extents":(1,100,1,100)}

# Case 2: Doesn't work
Case2={"id":2,
       "interp":"none",
       "extents":(tMin,tMax,1,100)}


for Case in (Case2, Case1, Case0):
    plt.figure(Case["id"])
    axImg=plt.subplot(111)
    axImg.imshow(imgData,
                    norm=LogNorm(),
                    interpolation=Case["interp"],
                    extent=Case["extents"])
    axImg.set_aspect('auto')

    for filetype in ["png", "eps", "pdf", "svg"]:
        plt.savefig("imageshift-Case{0}.{1}".format(Case["id"], filetype))



On Tue, Aug 14, 2012 at 3:19 AM, Eric Firing <ef...@ha...> wrote:

> On 2012/08/13 3:58 PM, Benjamin Root wrote:
> >
> >
> > On Thu, Aug 2, 2012 at 7:21 PM, Chad Parker <par...@gm...
> > <mailto:par...@gm...>> wrote:
> >
> >     Hello everyone-
> >
> >     I'm a new Python/Matplotlib user, but I have quite a bit of plotting
> >     experience with octave/matlab and gnuplot. So, I apologize in
> >     advance if my python style is terrible and if I give you all the
> >     wrong information!
> >
> >     I'm having a problem saving figures that contain images as eps files
> >     when my x-axis is a date/time axis. The trouble is that in the
> >     resulting eps file, the image data is shifted relative to the axis.
> >     I've attached two images as an example. In the .png file the
> >     alignment is correct and in the eps file it's not. The png is also
> >     nearly identical to what I get when I plot to the screen. The script
> >     I wrote to generate these plots is at the end of this message.
> >
> >     It's worth noting that the two output images are identical if the
> >     x-axis is simply numerical and not a time series.
> >
> >     I'm using python 2.7.3 and Matplotlib 1.1.0
> >
> >     Some Google searches dug up this old thread, however, the shift that
> >     I'm experiencing seems to be much greater, so I don't know if it's
> >     related:
> >
> http://old.nabble.com/Saving-as-eps-file-shifts-image--td29232680.html
> >
> >     Can anyone help me solve this?
> >     Thanks in advance,
> >     --Chad
> >
> >
> >     Here is a minimal script that I used to generate these plots:
> >
> >     import matplotlib.pyplot as plt
> >     import matplotlib.dates as dts
> >     from matplotlib.colors import LogNorm
> >
> >     imgData = [[1.0/x + 1.0/y for x in range(1,100)] for y in
> range(1,100)]
> >
> >     tMin=dts.epoch2num(1343947266)
> >     tMax=dts.epoch2num(1343947266+100)
> >
> >     axImg=plt.subplot(111)
> >     axImg.imshow(imgData, norm=LogNorm(),extent=(tMin,tMax,1,100),\
> >                      interpolation='none', origin="upper")
> >     axImg.xaxis_date()
> >     axImg.set_aspect('auto')
> >
> >     plt.savefig("imageshift.png")
> >     plt.savefig("imageshift.eps")
> >
> >
> > Confirmed.  This is a fairly nasty-looking result.  And I am not exactly
> > sure what is happening here.  Note that it does not matter if the png or
> > the eps images were saved first.  It looks like an auto-scaling bug, but
> > given that it doesn't impact the png image, I am not so sure.
>
> This appears to be some sort of truncation error bug; it has nothing to
> do with dates.  Here is a modified illustration:
>
> import matplotlib.pyplot as plt
> from matplotlib.colors import LogNorm
>
> imgData = [[1.0/x + 1.0/y for x in range(1,10)] for y in range(1,10)]
>
> tMin = 1000000066 # Shifted by half
> tMin = 100000066  # Blank!
> tMin = 10000066   # OK
> tMax = tMin+10
>
> # The following combination is also shifted by half
> tMin = 10000066.1  # adding the 0.1 doesn't make a difference
> tMax = tMin+1
>
> print tMin, tMax
>
> axImg=plt.subplot(111)
> axImg.imshow(imgData, norm=LogNorm(), extent=(tMin,tMax,1,10),
>                  interpolation='none', origin="upper")
> axImg.set_aspect('auto')
>
> plt.savefig("imageshift.png")
> plt.savefig("imageshift.eps")
> plt.savefig("imageshift.pdf")
>
> I thought it might come from the use of str() instead of repr() when
> generating the concat matrix in the ps backend, but that's not it.  I'm
> suspecting it may be inherent in the ps language, when one uses a matrix
> to make an enormous translation in one direction, and then uses
> translate to sling everything back in the other direction.  Either that,
> or some sort of "snapping" is going on.
>
> Eric
>
> >
> > Could you file a bug report on this at the github tracker?  I would like
> > to see this fixed before the 1.2.0 release.
> >
> > Thanks!
> > Ben Root
> >
>
>
>
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>

On 2012/08/13 3:58 PM, Benjamin Root wrote:
>
>
> On Thu, Aug 2, 2012 at 7:21 PM, Chad Parker <par...@gm...
> <mailto:par...@gm...>> wrote:
>
>     Hello everyone-
>
>     I'm a new Python/Matplotlib user, but I have quite a bit of plotting
>     experience with octave/matlab and gnuplot. So, I apologize in
>     advance if my python style is terrible and if I give you all the
>     wrong information!
>
>     I'm having a problem saving figures that contain images as eps files
>     when my x-axis is a date/time axis. The trouble is that in the
>     resulting eps file, the image data is shifted relative to the axis.
>     I've attached two images as an example. In the .png file the
>     alignment is correct and in the eps file it's not. The png is also
>     nearly identical to what I get when I plot to the screen. The script
>     I wrote to generate these plots is at the end of this message.
>
>     It's worth noting that the two output images are identical if the
>     x-axis is simply numerical and not a time series.
>
>     I'm using python 2.7.3 and Matplotlib 1.1.0
>
>     Some Google searches dug up this old thread, however, the shift that
>     I'm experiencing seems to be much greater, so I don't know if it's
>     related:
>     http://old.nabble.com/Saving-as-eps-file-shifts-image--td29232680.html
>
>     Can anyone help me solve this?
>     Thanks in advance,
>     --Chad
>
>
>     Here is a minimal script that I used to generate these plots:
>
>     import matplotlib.pyplot as plt
>     import matplotlib.dates as dts
>     from matplotlib.colors import LogNorm
>
>     imgData = [[1.0/x + 1.0/y for x in range(1,100)] for y in range(1,100)]
>
>     tMin=dts.epoch2num(1343947266)
>     tMax=dts.epoch2num(1343947266+100)
>
>     axImg=plt.subplot(111)
>     axImg.imshow(imgData, norm=LogNorm(),extent=(tMin,tMax,1,100),\
>                      interpolation='none', origin="upper")
>     axImg.xaxis_date()
>     axImg.set_aspect('auto')
>
>     plt.savefig("imageshift.png")
>     plt.savefig("imageshift.eps")
>
>
> Confirmed.  This is a fairly nasty-looking result.  And I am not exactly
> sure what is happening here.  Note that it does not matter if the png or
> the eps images were saved first.  It looks like an auto-scaling bug, but
> given that it doesn't impact the png image, I am not so sure.

This appears to be some sort of truncation error bug; it has nothing to 
do with dates.  Here is a modified illustration:

import matplotlib.pyplot as plt
from matplotlib.colors import LogNorm

imgData = [[1.0/x + 1.0/y for x in range(1,10)] for y in range(1,10)]

tMin = 1000000066 # Shifted by half
tMin = 100000066  # Blank!
tMin = 10000066   # OK
tMax = tMin+10

# The following combination is also shifted by half
tMin = 10000066.1  # adding the 0.1 doesn't make a difference
tMax = tMin+1

print tMin, tMax

axImg=plt.subplot(111)
axImg.imshow(imgData, norm=LogNorm(), extent=(tMin,tMax,1,10),
                 interpolation='none', origin="upper")
axImg.set_aspect('auto')

plt.savefig("imageshift.png")
plt.savefig("imageshift.eps")
plt.savefig("imageshift.pdf")

I thought it might come from the use of str() instead of repr() when 
generating the concat matrix in the ps backend, but that's not it.  I'm 
suspecting it may be inherent in the ps language, when one uses a matrix 
to make an enormous translation in one direction, and then uses 
translate to sling everything back in the other direction.  Either that, 
or some sort of "snapping" is going on.

Eric

>
> Could you file a bug report on this at the github tracker?  I would like
> to see this fixed before the 1.2.0 release.
>
> Thanks!
> Ben Root
>

On Thu, Aug 2, 2012 at 7:21 PM, Chad Parker <par...@gm...>wrote:

> Hello everyone-
>
> I'm a new Python/Matplotlib user, but I have quite a bit of plotting
> experience with octave/matlab and gnuplot. So, I apologize in advance if my
> python style is terrible and if I give you all the wrong information!
>
> I'm having a problem saving figures that contain images as eps files when
> my x-axis is a date/time axis. The trouble is that in the resulting eps
> file, the image data is shifted relative to the axis. I've attached two
> images as an example. In the .png file the alignment is correct and in the
> eps file it's not. The png is also nearly identical to what I get when I
> plot to the screen. The script I wrote to generate these plots is at the
> end of this message.
>
> It's worth noting that the two output images are identical if the x-axis
> is simply numerical and not a time series.
>
> I'm using python 2.7.3 and Matplotlib 1.1.0
>
> Some Google searches dug up this old thread, however, the shift that I'm
> experiencing seems to be much greater, so I don't know if it's related:
> http://old.nabble.com/Saving-as-eps-file-shifts-image--td29232680.html
>
> Can anyone help me solve this?
> Thanks in advance,
> --Chad
>
>
> Here is a minimal script that I used to generate these plots:
>
> import matplotlib.pyplot as plt
> import matplotlib.dates as dts
> from matplotlib.colors import LogNorm
>
> imgData = [[1.0/x + 1.0/y for x in range(1,100)] for y in range(1,100)]
>
> tMin=dts.epoch2num(1343947266)
> tMax=dts.epoch2num(1343947266+100)
>
> axImg=plt.subplot(111)
> axImg.imshow(imgData, norm=LogNorm(),extent=(tMin,tMax,1,100),\
>                 interpolation='none', origin="upper")
> axImg.xaxis_date()
> axImg.set_aspect('auto')
>
> plt.savefig("imageshift.png")
> plt.savefig("imageshift.eps")
>
>
Confirmed.  This is a fairly nasty-looking result.  And I am not exactly
sure what is happening here.  Note that it does not matter if the png or
the eps images were saved first.  It looks like an auto-scaling bug, but
given that it doesn't impact the png image, I am not so sure.

Could you file a bug report on this at the github tracker?  I would like to
see this fixed before the 1.2.0 release.

Thanks!
Ben Root

On Sun, Aug 12, 2012 at 01:23:35PM -0700, jonasr wrote:
> Hello, 
> 
> i am working on some 3d stuff with plot_surface() , my problem is that  i
> want to use a stride smaller then 1.

The stride refers to the *array* stride. So a stride of < 1 makes no
sense.

> Since my data is only on an intervall from -1 to 1, in x and in y direction
> i want to plot a 3d grid with at least 20 lines in each direction, is there
> a possibility to do this ?

An rstride of 1 will plot every row. A cstride of 3 will plot every 3rd
column. If your data is in a 2D array of dimensions 100x100, say, then
setting rstride=5 and cstride=5 will plot every 5th row and every 5th
column, giving 20 lines in each direction. The kwargs rstride and
cstride do not care about the domain of your data.

Hope this helps.

-- 
Damon McDougall
http://www.damon-is-a-geek.com
B2.39
Mathematics Institute
University of Warwick
Coventry
West Midlands
CV4 7AL
United Kingdom

Hi Ben,

On Sat, Aug 11, 2012 at 8:30 AM, Benjamin Root <ben...@ou...> wrote:
> I have said this before, and it can't be repeated often enough.  The work
> that you and your team has been doing the past few years with the notebook
> is *already* revolutionizing how we teach python.  10 years from now,
> programmers will point to this as the *killer* feature of python.

well, your kind words are very much appreciated, truly.  It's been a
ton of work, and at this point far more credit goes to the rest of the
team than to me.

One thing I'd like to emphasize is how strong, productive and positive
the collaboration between IPython and matplotlib has been over time:
we have managed to allow both projects to fully retain their identity
(we don't even have a hard dependency on mpl in IPython, and
matplotlib doesn't even import IPython at all), and yet the two
projects complement each other very well, benefiting both of them, and
ultimately all of our users.  A good combination of communication and
collaboration has allowed us to maintain a strong separation of
concerns while providing users a feel of integrated functionality
where it matters.

I have every reason to believe that, as we push into the second decade
of this effort with the vision of challenges and ideas that John and
Michael D. recently laid out (at the SciPy'12 keynote and in Michael's
posts), this is only going to get better.  The web work is going to be
a pretty tough challenge, but at the same time it's a great
opportunity to revisit key parts of matplotlib with a lot of hindsight
we've accumulated.

That kind of hindsight is what let us refactor all of IPython over the
last few years, so that while the user experience at the terminal from
0.10 to 0.11 remained mostly unchanged (we did have some regressions
but they were pretty mild), we had a completely new architecture under
the hood that paved the way for the qt console, the notebook and the
current parallel machinery.  I hope we'll see similar benefits as the
web forces us to rethink matplotlib for a multiprocess model.

Cheers,

f

Hello, 

i am working on some 3d stuff with plot_surface() , my problem is that  i
want to use a stride smaller then 1.
Since my data is only on an intervall from -1 to 1, in x and in y direction
i want to plot a 3d grid with at least 20 lines in each direction, is there
a possibility to do this ?

thanks  



--
View this message in context: http://matplotlib.1069221.n5.nabble.com/Stride-size-in-mplot3d-tp38500.html
Sent from the matplotlib - users mailing list archive at Nabble.com.

Hi All,

  I would like to know if there is a way to have the bin sizes change by
integer values. For example the bin size would be
 10-20
 20-30

not 

10.3-20.5
20.3-30.5

and have it adjust as the number of bins changes.
Thanks 



--
View this message in context: http://matplotlib.1069221.n5.nabble.com/Set-Histogram-bin-size-to-change-by-interger-value-tp38499.html
Sent from the matplotlib - users mailing list archive at Nabble.com.

On Saturday, August 11, 2012, Fernando Perez wrote:

> On Sat, Aug 11, 2012 at 12:09 AM, Nicolas Rougier
> <Nic...@in... <javascript:;>> wrote:
> > By the way, I suspect the simple plot part may well suited for the
> ipython notebook !
> > I'll give it a try.
>
> Actually in the notebook it is now possible to enable exercises,
> hints, reveal-boxes, etc.  I'm cc'ing here Matthias Bussonnier b/c I'm
> not sure if he's on the mpl list.  He's one of our recent core devs
> who is behind a lot of our new JS magic in the notebook, and he's also
> a French scientist who will be at Euroscipy, so you guys could perhaps
> touch bases (I'm unfortunately not going to make it this year).
>
> Ultimately we'd like to make it very easy to write tutorials such as
> yours directly as notebooks, so that when used in the classroom
> students can work straight off them, and yet also publish then with
> clean and customizable HTML on the web like you did.  Lots of the
> pieces are in place, though not quite all yet :)
>
> Cheers,
>
> f


Fernando,

I have said this before, and it can't be repeated often enough.  The work
that you and your team has been doing the past few years with the notebook
is *already* revolutionizing how we teach python.  10 years from now,
programmers will point to this as the *killer* feature of python.

Kudos!
Ben Root

On 10/08/2012 21:27, Damon McDougall wrote:

[snipped]

>
> Actually, I discovered today that this is possible. You can use step()
> to achieve what you want:
>
> http://matplotlib.sourceforge.net/examples/pylab_examples/step_demo.html
>

Awesome, my question answered before I'd even asked it :)

-- 
Cheers.

Mark Lawrence.

Le 11 août 2012 à 10:43, Nicolas Rougier a écrit :

> 
> 
> Fantastic ! This is very valuable teaching material.
> Really great job and big thanks to all the ipython developers.
> 
> Matthias, hope to see you at Euroscipy (and see some ipython demos).
> In fact, I've also some questions around ipython/webgl for you...
Hi, 
I haven't read the all thread yet, 
but for what we did at SciPy Texas, we achieved some prototype of 
	Encrypted cells, 
	Hidable Cells, 
	Cell with custom background depending on type (green for numpy example...etc) 
And a presentation mode that showed cell by blocks. 

This should be doable much more easily now that notebook support custom Js/Css on a per profile basis.

Also i'll be out of reach from the 15 to the 20 so if you have any question i'll try to respond to you quickly. 
--
Matthias



Some experimental branches.

--those are the same at difference states.
https://github.com/Carreau/ipython/tree/_pmode 
https://github.com/Carreau/ipython/tree/_Pmode
https://github.com/Carreau/ipython/tree/rebase_slideshow_extension
https://github.com/Carreau/ipython/tree/slideshow_extension
https://github.com/Carreau/ipython/tree/_slide_mode

--this one should show you how to make encrypted cell.
https://github.com/Carreau/ipython/tree/cryptcell



> Nicolas
> 
> 
> On Aug 11, 2012, at 9:17 , Fernando Perez wrote:
> 
>> On Sat, Aug 11, 2012 at 12:09 AM, Nicolas Rougier
>> <Nic...@in...> wrote:
>>> By the way, I suspect the simple plot part may well suited for the ipython notebook !
>>> I'll give it a try.
>> 
>> Actually in the notebook it is now possible to enable exercises,
>> hints, reveal-boxes, etc.  I'm cc'ing here Matthias Bussonnier b/c I'm
>> not sure if he's on the mpl list.  He's one of our recent core devs
>> who is behind a lot of our new JS magic in the notebook, and he's also
>> a French scientist who will be at Euroscipy, so you guys could perhaps
>> touch bases (I'm unfortunately not going to make it this year).
>> 
>> Ultimately we'd like to make it very easy to write tutorials such as
>> yours directly as notebooks, so that when used in the classroom
>> students can work straight off them, and yet also publish then with
>> clean and customizable HTML on the web like you did.  Lots of the
>> pieces are in place, though not quite all yet :)
>> 
>> Cheers,
>> 
>> f
> 

Fantastic ! This is very valuable teaching material.
Really great job and big thanks to all the ipython developers.

Matthias, hope to see you at Euroscipy (and see some ipython demos).
In fact, I've also some questions around ipython/webgl for you...


Nicolas


On Aug 11, 2012, at 9:17 , Fernando Perez wrote:

> On Sat, Aug 11, 2012 at 12:09 AM, Nicolas Rougier
> <Nic...@in...> wrote:
>> By the way, I suspect the simple plot part may well suited for the ipython notebook !
>> I'll give it a try.
> 
> Actually in the notebook it is now possible to enable exercises,
> hints, reveal-boxes, etc.  I'm cc'ing here Matthias Bussonnier b/c I'm
> not sure if he's on the mpl list.  He's one of our recent core devs
> who is behind a lot of our new JS magic in the notebook, and he's also
> a French scientist who will be at Euroscipy, so you guys could perhaps
> touch bases (I'm unfortunately not going to make it this year).
> 
> Ultimately we'd like to make it very easy to write tutorials such as
> yours directly as notebooks, so that when used in the classroom
> students can work straight off them, and yet also publish then with
> clean and customizable HTML on the web like you did.  Lots of the
> pieces are in place, though not quite all yet :)
> 
> Cheers,
> 
> f

On Sat, Aug 11, 2012 at 12:09 AM, Nicolas Rougier
<Nic...@in...> wrote:
> By the way, I suspect the simple plot part may well suited for the ipython notebook !
> I'll give it a try.

Actually in the notebook it is now possible to enable exercises,
hints, reveal-boxes, etc.  I'm cc'ing here Matthias Bussonnier b/c I'm
not sure if he's on the mpl list.  He's one of our recent core devs
who is behind a lot of our new JS magic in the notebook, and he's also
a French scientist who will be at Euroscipy, so you guys could perhaps
touch bases (I'm unfortunately not going to make it this year).

Ultimately we'd like to make it very easy to write tutorials such as
yours directly as notebooks, so that when used in the classroom
students can work straight off them, and yet also publish then with
clean and customizable HTML on the web like you did.  Lots of the
pieces are in place, though not quite all yet :)

Cheers,

f

Thanks Fernando !

By the way, I suspect the simple plot part may well suited for the ipython notebook !
I'll give it a try.


Nicolas



On Aug 11, 2012, at 4:55 , Fernando Perez wrote:

> On Fri, Aug 10, 2012 at 5:23 AM, Nicolas Rougier
> <Nic...@in...> wrote:
>> 
>> I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:
>> 
>> http://www.loria.fr/~rougier/teaching/matplotlib/
> 
> Wow!  Other than the rendering glitches already mentioned, this is
> *awesome*.  We're teaching a python workshop at UC Berkeley in 2 weeks
> (http://register.pythonbootcamp.info) and I just suggested we use this
> for our mpl intro.
> 
> It's the best one I've seen so far, and the reference info at the
> bottom as well as the mini-gallery will make it a very useful resource
> even for seasoned users.
> 
> Fantastic job, Nicolas (and Mike M.), and thanks for sharing this
> great resource!
> 
> Cheers,
> 
> f

On Fri, Aug 10, 2012 at 5:23 AM, Nicolas Rougier
<Nic...@in...> wrote:
>
> I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:
>
> http://www.loria.fr/~rougier/teaching/matplotlib/

Wow!  Other than the rendering glitches already mentioned, this is
*awesome*.  We're teaching a python workshop at UC Berkeley in 2 weeks
(http://register.pythonbootcamp.info) and I just suggested we use this
for our mpl intro.

It's the best one I've seen so far, and the reference info at the
bottom as well as the mini-gallery will make it a very useful resource
even for seasoned users.

Fantastic job, Nicolas (and Mike M.), and thanks for sharing this
great resource!

Cheers,

f

On Fri, Aug 10, 2012 at 12:47:22PM +0100, Damon McDougall wrote:
> On Fri, Aug 10, 2012 at 02:09:39PM +0530, satish maurya wrote:
> > Dear All,
> > 
> > I want to stairs plot (similar in matlab) matplotlib
> > First i want for i data-set then multiple data-set super impose on that.
> > I attach the figure it's showing velocity-depth stairs plots for
> > superimpose (like hold on in matlab)
> > large data-set.
> > can anybody tell me how to plot that.
> >
> 
> I'm not sure I understand what you're asking. Are you asking how to make
> a stairplot, or are you asking how to make *multiple* plots on one set
> of axes?
> 
> If your question is the former, matplotlib does not currently have a
> stairplot implementation, but it wouldn't be hard to use the usual
> plot() function to achieve the desired effect:
>

Actually, I discovered today that this is possible. You can use step()
to achieve what you want:

http://matplotlib.sourceforge.net/examples/pylab_examples/step_demo.html

> 
> Before:
> 
> x = arange(0, 10, 1)
> y = x * (10.0 - x)
> plot(x, y)
> 
> After:
> 
> x = arange(0, 10, 1)
> x_m = x - 0.5 # left-hand midpoints
> x_p = x + 0.5 # right-hand midpoints
> y = x * (10.0 - x)
> x_all = dstack((x_m, x, x_p)).flatten()
> y_all = dstack((y, y, y)).flatten()
> plot(x_all, y_all)
> 
> If your question is the latter, you can toggle the hold state just by
> calling
> 
> hold()
> 
> Hope this helps.
> 
> > 
> > see the figure
> > 
> > Thank you
> > 
> > -- 
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > *Satish Maurya*
> > *Research Scholar*
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> -- 
> Damon McDougall
> http://damon-is-a-geek.com
> B2.39
> Mathematics Institute
> University of Warwick
> Coventry
> West Midlands
> CV4 7AL
> United Kingdom

-- 
Damon McDougall
http://damon-is-a-geek.com
B2.39
Mathematics Institute
University of Warwick
Coventry
West Midlands
CV4 7AL
United Kingdom

Not at all of course. Glad this might be of some help for matplolib.


Nicolas


On Aug 10, 2012, at 16:03 , Michael Droettboom wrote:

> Very nice.  I'm thinking of some ideas to revamp the 
> documentation/website, and one thing I would like to do is to link to 
> some of these external resources.  Do you have any objections to me 
> linking to this?
> 
> Mike
> 
> On 08/10/2012 08:23 AM, Nicolas Rougier wrote:
>> 
>> Hi all,
>> 
>> 
>> I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:
>> 
>> http://www.loria.fr/~rougier/teaching/matplotlib/
>> 
>> 
>> It is based on Mike Müller tutorial from scipy lecture notes (http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
>> 
>> Sources are available from: https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
>> 
>> 
>> If you've any comments or see errors...
>> 
>> 
>> 
>> Nicolas
>> ------------------------------------------------------------------------------
>> Live Security Virtual Conference
>> Exclusive live event will cover all the ways today's security and
>> threat landscape has changed and how IT managers can respond. Discussions
>> will include endpoint security, mobile security and the latest in malware
>> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
>> _______________________________________________
>> Matplotlib-users mailing list
>> Mat...@li...
>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users
> 
> 
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and 
> threat landscape has changed and how IT managers can respond. Discussions 
> will include endpoint security, mobile security and the latest in malware 
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Thanks, just forgot about the license. It will be the same as the scipy lecture notes which is a 

Creative Commons Attribution 3.0 United States License (CC-by)
http://creativecommons.org/licenses/by/3.0/us

Would that be ok or is a BSD one more suited ?


Nicolas


On Aug 10, 2012, at 15:10 , Benjamin Root wrote:

> 
> 
> On Fri, Aug 10, 2012 at 8:23 AM, Nicolas Rougier <Nic...@in...> wrote:
> 
> 
> Hi all,
> 
> 
> I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:
> 
> http://www.loria.fr/~rougier/teaching/matplotlib/
> 
> 
> It is based on Mike Müller tutorial from scipy lecture notes (http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
> 
> Sources are available from: https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
> 
> 
> If you've any comments or see errors...
> 
> 
> 
> Nicolas
> 
> Nice work.  I haven't read through all of it yet, but I did notice a layout issue in firefox (using 10.0.4).  Many of the code snippets are being placed on top of the example image.
> 
> What is the license for this tutorial?  You should also place some copyright info at the bottom as well.
> 
> Cheers!
> Ben Root
> 

Thank you all, I will try to correct that.
I developed it in full screen mode and did not paid attention to the layout.

Nicolas


On Aug 10, 2012, at 15:33 , Fabrice Silva wrote:

> Le vendredi 10 août 2012 à 14:19 +0100, Damon McDougall a écrit :
>> On Fri, Aug 10, 2012 at 09:10:15AM -0400, Benjamin Root wrote:
>>> 
>>> Nice work.  I haven't read through all of it yet, but I did notice a layout
>>> issue in firefox (using 10.0.4).  Many of the code snippets are being
>>> placed on top of the example image.
>> 
>> I see this behaviour too, on Chrome, version 20.0.1132.57.
> 
> Same on epiphany 3.4.2 (webkit 1.8.1)
> 
> -- 
> Fabrice Silva
> 
> 
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and 
> threat landscape has changed and how IT managers can respond. Discussions 
> will include endpoint security, mobile security and the latest in malware 
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

Very nice.  I'm thinking of some ideas to revamp the 
documentation/website, and one thing I would like to do is to link to 
some of these external resources.  Do you have any objections to me 
linking to this?

Mike

On 08/10/2012 08:23 AM, Nicolas Rougier wrote:
>
> Hi all,
>
>
> I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:
>
> http://www.loria.fr/~rougier/teaching/matplotlib/
>
>
> It is based on Mike Müller tutorial from scipy lecture notes (http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
>
> Sources are available from: https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
>
>
> If you've any comments or see errors...
>
>
>
> Nicolas
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Matplotlib-users mailing list
> Mat...@li...
> https://lists.sourceforge.net/lists/listinfo/matplotlib-users

On Fri, Aug 10, 2012 at 8:23 AM, Nicolas Rougier
<Nic...@in...>wrote:

>
>
> Hi all,
>
>
> I've just finished a new introductory tutorial for incoming Euroscipy
> 2012. You can find it here:
>
> http://www.loria.fr/~rougier/teaching/matplotlib/
>
>
> It is based on Mike Müller tutorial from scipy lecture notes (
> http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
>
> Sources are available from:
> https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
>
>
> If you've any comments or see errors...
>
>
>
> Nicolas
>
>
This is really beautifully presented. It would be great if some, or all of
this could be integrated into the main Matplotlib site. Someone emailed the
list not too long suggesting that the user guide was geared more toward
developers. This tutorial would definitely fill the gap.

If nothing else, I would love to see the "Other types of plots" and "Quick
Reference" sections as pages on the main site with links to them on the
main navigation bar.

Nice work!
-Tony

Le vendredi 10 août 2012 à 14:19 +0100, Damon McDougall a écrit :
> On Fri, Aug 10, 2012 at 09:10:15AM -0400, Benjamin Root wrote:
> > 
> > Nice work.  I haven't read through all of it yet, but I did notice a layout
> > issue in firefox (using 10.0.4).  Many of the code snippets are being
> > placed on top of the example image.
> 
> I see this behaviour too, on Chrome, version 20.0.1132.57.

Same on epiphany 3.4.2 (webkit 1.8.1)

-- 
Fabrice Silva

On Fri, Aug 10, 2012 at 09:10:15AM -0400, Benjamin Root wrote:
> On Fri, Aug 10, 2012 at 8:23 AM, Nicolas Rougier
> <Nic...@in...>wrote:
> 
> >
> > Hi all,
> >
> > I've just finished a new introductory tutorial for incoming Euroscipy
> > 2012. You can find it here:
> >
> > http://www.loria.fr/~rougier/teaching/matplotlib/
> >
> > It is based on Mike Müller tutorial from scipy lecture notes (
> > http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
> >
> > Sources are available from:
> > https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
> >
> > If you've any comments or see errors...
> >
> > Nicolas
> >
> 
> Nice work.  I haven't read through all of it yet, but I did notice a layout
> issue in firefox (using 10.0.4).  Many of the code snippets are being
> placed on top of the example image.
>

I see this behaviour too, on Chrome, version 20.0.1132.57.

Tutorial  looks nice, though :)

-- 
Damon McDougall
http://damon-is-a-geek.com
B2.39
Mathematics Institute
University of Warwick
Coventry
West Midlands
CV4 7AL
United Kingdom

On Fri, Aug 10, 2012 at 8:23 AM, Nicolas Rougier
<Nic...@in...>wrote:

>
>
> Hi all,
>
>
> I've just finished a new introductory tutorial for incoming Euroscipy
> 2012. You can find it here:
>
> http://www.loria.fr/~rougier/teaching/matplotlib/
>
>
> It is based on Mike Müller tutorial from scipy lecture notes (
> http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)
>
> Sources are available from:
> https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012
>
>
> If you've any comments or see errors...
>
>
>
> Nicolas
>

Nice work.  I haven't read through all of it yet, but I did notice a layout
issue in firefox (using 10.0.4).  Many of the code snippets are being
placed on top of the example image.

What is the license for this tutorial?  You should also place some
copyright info at the bottom as well.

Cheers!
Ben Root

Hi all,


I've just finished a new introductory tutorial for incoming Euroscipy 2012. You can find it here:

http://www.loria.fr/~rougier/teaching/matplotlib/


It is based on Mike Müller tutorial from scipy lecture notes (http://scipy-lectures.github.com/intro/matplotlib/matplotlib.html)

Sources are available from: https://github.com/rougier/scipy-lecture-notes/tree/euroscipy-2012


If you've any comments or see errors...



Nicolas

On Fri, Aug 10, 2012 at 02:09:39PM +0530, satish maurya wrote:
> Dear All,
> 
> I want to stairs plot (similar in matlab) matplotlib
> First i want for i data-set then multiple data-set super impose on that.
> I attach the figure it's showing velocity-depth stairs plots for
> superimpose (like hold on in matlab)
> large data-set.
> can anybody tell me how to plot that.
>

I'm not sure I understand what you're asking. Are you asking how to make
a stairplot, or are you asking how to make *multiple* plots on one set
of axes?

If your question is the former, matplotlib does not currently have a
stairplot implementation, but it wouldn't be hard to use the usual
plot() function to achieve the desired effect:

Before:

x = arange(0, 10, 1)
y = x * (10.0 - x)
plot(x, y)

After:

x = arange(0, 10, 1)
x_m = x - 0.5 # left-hand midpoints
x_p = x + 0.5 # right-hand midpoints
y = x * (10.0 - x)
x_all = dstack((x_m, x, x_p)).flatten()
y_all = dstack((y, y, y)).flatten()
plot(x_all, y_all)

If your question is the latter, you can toggle the hold state just by
calling

hold()

Hope this helps.

> 
> see the figure
> 
> Thank you
> 
> -- 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> *Satish Maurya*
> *Research Scholar*
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

-- 
Damon McDougall
http://damon-is-a-geek.com
B2.39
Mathematics Institute
University of Warwick
Coventry
West Midlands
CV4 7AL
United Kingdom