matplotlib-users Mailing List for matplotlib (Page 7)

Dear all,

Does anyone have similar experience that to make a colorbar
starting from a different color in the colormap? for example, to
denote the region with invalid data. I attahced a figure to show
what I would like to have, the withe region in the colorbar in the
attahced figure shows no data.

thanks a lot for any help,

best,

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
************************************************************************************

Dear all matplotlib users,

I found there is not a get_ticks method available for colorbar instance,
how could I quick get the ticks of a colorbar?

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
************************************************************************************

On 1 July 2013 13:40, zetah <ot...@hu...> wrote:

> Hi,
>
> I have set of points in a plane and make triplot:
>
>     subplot(121)
>     plot(points[:,0], points[:,1], 'o')
>     title('Set of points')
>     subplot(122)
>     triplot(points[:,0], points[:,1])
>     title('Triangulation')
>
> result: http://i.imgur.com/1LG4fxC.png
>
> Does anyone know how to extract just the lines describing each
> circumscribed circle in this example?
> Perhaps by using Delaunay from scipy.spatial?
>
> Just to inform you, I want to do this through triangulation and above
> example is trivial that can be solved differently, while real problem
> doesn't contain circles...
>

You need to use a matplotlib.tri.Triangulation (your use of triplot does
this for you behind the scenes anyway), something like:

import matplotlib.tri as mtri
triang = mtri.Triangulation(xpoints, ypoints)

Now triang.triangles is an array of integers of shape (?, 3) such that
triang.triangles[i,:] are the three indices of the points that comprise
triangle i.  You will need to use these to determine the information you
want.  The triplot example (
http://matplotlib.org/examples/pylab_examples/triplot_demo.html) does
something similar, identifying which triangles are within a particular
circle; I guess in your case a simple approach would be to test if the
distance from the centre of each triangle edge to your circle of interest
is below some threshold or not.

Incidentally, if you have a Triangulation object then subsequent calls to
functions like triplot can be of the form triplot(triang), which will be
faster than repeated calls to triplot(xpoints, ypoints) as in the latter
case a separate Delaunay triangulation needs to be performed for each
triplot call.

Ian

William Ray Wing wrote
> On Jul 1, 2013, at 1:42 PM, psb1967 <

> psb67@

> > wrote:
> 
> 
> Suresh,  I think the most likely reason no one has answered is that the
> intersection of the set of matplotlib experts and the set of people who
> know what Bollinger bands are is too close to zero.  I'm a beginner at
> matplotlib, but I do know what Bollinger bands are, and I'd suggest your
> best approach is to take a look at the matplotlib demo gallery here:  
> 
> http://matplotlib.org/examples
> 
> in particular, study the code for the fifth example from the top here: 
> http://matplotlib.org/examples/pylab_examples/plotfile_demo.html
> 
> which implements a plot of Open, High. Low, and Closing prices.  I'm
> assuming you know enough math to implement a Bollinger band version of a
> moving average, and can just substitute it for the code that plots the
> extra lines on the example.
> 
> Good luck,
> Bill

Hi Bill,

I am truly overwhelmed to see the kind of efforts taken to guide when one
requires guidance, esp. the fresh programmers. One of the things that I
learned when no one responds with a specific answer but shown the direction
is that I am given an opportunity to learn and work  by myself. I really
appreciate your time and will start working on the example you have cited.

In fact, I did get a complete Bollinger bands script however, I will start
working on the line you have shown; it may open up new avenues. 

Regards.

Suresh



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View this message in context: http://matplotlib.1069221.n5.nabble.com/To-add-Bollinger-Bands-in-finance-work2-py-tp41310p41359.html
Sent from the matplotlib - users mailing list archive at Nabble.com.

Hi all,

after John's untimely passing we had a memorial service in Chicago,
but only a few on these lists were able to attend. At last week's
scipy conference I read a slightly edited version of the eulogy from
that memorial service, and I figured some of you might be interested
if you missed the conference:

http://blog.fperez.org/2013/07/in-memoriam-john-d-hunter-iii-1968-2012.html

Cheers,

f

--
Fernando Perez (@fperez_org; http://fperez.org)
fperez.net-at-gmail: mailing lists only (I ignore this when swamped!)
fernando.perez-at-berkeley: contact me here for any direct mail

On Jul 1, 2013, at 1:42 PM, psb1967 <ps...@ho...> wrote:

> Hi Ben,
> 
> 
> Benjamin Root-2 wrote
>> On Sun, Jun 23, 2013 at 6:29 AM, psb1967 &lt;
> 
>> psb67@
> 
>> &gt; wrote:
>> 
>> 
>>> 
>> Since nobody has replied, I would suggest asking your question on the
>> scipy
>> users list, which is more geared towards implementation of various
>> algorithms. The matplotlib mailing list mostly deals with plotting
>> questions.  When you need help with plotting your results, let us know!
>> 
>> Cheers!
>> Ben Root
> 
> May be it was my mistake posting a wrong request, without properly
> understanding the nature of this elite site, nevertheless, I am grateful for
> your taking time to reply and guide me in the proper direction.
> 
> I will give it a try with scipy user list.
> 
> Regards
> 
> Suresh
> 
> 

Suresh,  I think the most likely reason no one has answered is that the intersection of the set of matplotlib experts and the set of people who know what Bollinger bands are is too close to zero.  I'm a beginner at matplotlib, but I do know what Bollinger bands are, and I'd suggest your best approach is to take a look at the matplotlib demo gallery here:  

http://matplotlib.org/examples

in particular, study the code for the fifth example from the top here:  http://matplotlib.org/examples/pylab_examples/plotfile_demo.html

which implements a plot of Open, High. Low, and Closing prices.  I'm assuming you know enough math to implement a Bollinger band version of a moving average, and can just substitute it for the code that plots the extra lines on the example.

Good luck,
Bill

Hi Ben,


Benjamin Root-2 wrote
> On Sun, Jun 23, 2013 at 6:29 AM, psb1967 <

> psb67@

> > wrote:
> 
> 
>>
> Since nobody has replied, I would suggest asking your question on the
> scipy
> users list, which is more geared towards implementation of various
> algorithms. The matplotlib mailing list mostly deals with plotting
> questions.  When you need help with plotting your results, let us know!
> 
> Cheers!
> Ben Root

May be it was my mistake posting a wrong request, without properly
understanding the nature of this elite site, nevertheless, I am grateful for
your taking time to reply and guide me in the proper direction.

I will give it a try with scipy user list.

Regards

Suresh




--
View this message in context: http://matplotlib.1069221.n5.nabble.com/To-add-Bollinger-Bands-in-finance-work2-py-tp41310p41355.html
Sent from the matplotlib - users mailing list archive at Nabble.com.

On Sun, Jun 23, 2013 at 6:29 AM, psb1967 <ps...@ho...> wrote:

> Hi,
>
> I am new to programming and this is my first major work.
>
> I wish to add Bollinger Bands and Hull Moving Average(HMA) in
> finance_work2.py. Need your guidance.
>
> Installation details:
>
> Windows 7
> Python 3.3.2
> Matplotlib 1.2.1
> Numpy 1.7.1
> Ta-Lib
>
> As it is I don't have any issues running the script however, adding BB and
> HMA will complete my task.
>
> Thanks in advance.
>
>
>
Since nobody has replied, I would suggest asking your question on the scipy
users list, which is more geared towards implementation of various
algorithms. The matplotlib mailing list mostly deals with plotting
questions.  When you need help with plotting your results, let us know!

Cheers!
Ben Root

SciPy 2013 was a great success.  I didn't get good headcount at the 
matplotlib BOF, but it was a good number, and we had 15 participants at 
various points during the sprints.  It was nice to see the diversity of 
experience with matplotlib at the sprints, and I hope we oldtimers were 
helpful to the newtimers getting started so they can continue to 
contribute in the future.  It was also great to put some faces to many 
of the talented names I've been seeing on github and the mailing list 
lately.

I've summarized the matplotlib BOF as well as the sprint.  I've also 
gone ahead and created MEP placeholders and issues for the major themes 
discussed.

https://github.com/matplotlib/matplotlib/wiki/Scipy-2013-BOF-Notes

https://github.com/matplotlib/matplotlib/wiki/Scipy-2013-sprinting-notes

Both of these documents are based on the realtime etherpad notes we made 
during the sessions, and on some of my own recollection, which is known 
to be incomplete or incorrect on occasion.  If I missed something, or 
you feel something isn't expressed in the right light, feel free to edit 
the wiki, but we should keep further discussion on the mailing list, 
github issues or other channels.  It would also be great to have 
volunteers to help write a MEP or two based on the BOF discussion.

Thanks again.  It was really nice to meet all of you!

Mike

Hi,

I have set of points in a plane and make triplot:

    subplot(121)
    plot(points[:,0], points[:,1], 'o')
    title('Set of points')
    subplot(122)
    triplot(points[:,0], points[:,1])
    title('Triangulation')

result: http://i.imgur.com/1LG4fxC.png

Does anyone know how to extract just the lines describing each circumscribed circle in this example?
Perhaps by using Delaunay from scipy.spatial?

Just to inform you, I want to do this through triangulation and above example is trivial that can be solved differently, while real problem doesn't contain circles...


Thanks