From: Jesper L. <jl...@dm...> - 2005-10-14 16:38:08
|
Hi matplotlib users, I have a long list of ungridded data that I would like to make a contour plot of. The data is simply a list of (longitude, latitude, datavalue) with the data value belonging the given longitude and latitude. As far as I understand contour() only accepts gridded data values. The solution is probably to interpolate the unstructured data to a regular grid and then plot the data. Has anyone tried doing that or know where to look for an interpolation/triangulation routine? Cheers, Jesper |
From: Jeff W. <js...@fa...> - 2005-10-14 17:27:47
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Jesper Larsen wrote: >Hi matplotlib users, > >I have a long list of ungridded data that I would like to make a contour plot >of. The data is simply a list of (longitude, latitude, datavalue) with the >data value belonging the given longitude and latitude. As far as I understand >contour() only accepts gridded data values. > >The solution is probably to interpolate the unstructured data to a regular >grid and then plot the data. Has anyone tried doing that or know where to >look for an interpolation/triangulation routine? > >Cheers, >Jesper > > > > Jesper: I've had good luck with the natgrid package in CDAT (http://cdat.sf.net). It will grid unstructured data for you. You can install it without installing the rest of CDAT, just go to the contrib/natgrid directory and run setup.py install. -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: Jeff W. <js...@fa...> - 2005-10-14 23:10:36
|
Jesper Larsen wrote: >Hi matplotlib users, > >I have a long list of ungridded data that I would like to make a contour plot >of. The data is simply a list of (longitude, latitude, datavalue) with the >data value belonging the given longitude and latitude. As far as I understand >contour() only accepts gridded data values. > >The solution is probably to interpolate the unstructured data to a regular >grid and then plot the data. Has anyone tried doing that or know where to >look for an interpolation/triangulation routine? > >Cheers, >Jesper > > > Jesper: Since this question has come up a couple of times, I decided to cook up an example. First you'll need to download and install the natgrid python module (included in CDAT, but I've separated it out from the huge tarball and put it at ftp://ftp.cdc.noaa.gov/Public/jsw/natgrid.tar.gz). Then try this: from RandomArray import uniform import pylab as p import nat def griddata(x,y,z,xi,yi): r = nat.Natgrid(y, x, yi, xi) return r.rgrd(z) npts = 500 x = uniform(-2,2,npts); y = uniform(-2,2,npts) z = x*p.exp(-x**2-y**2) # x, y, and z are now vectors containing nonuniformly sampled data. # Define a regular grid and grid data to it. nx = 51; ny = 41 x1 = p.linspace(-2,2,nx) y1 = p.linspace(-2,2,ny) xi, yi = p.meshgrid(x1, y1) zi = griddata(x,y,z,x1,y1) # Contour the gridded data, plotting dots at the nonuniform data points. CS = p.contour(xi,yi,zi,15,linewidths=0.5,colors=['k']) CS = p.contourf(xi,yi,zi,15,cmap=p.cm.jet) p.scatter(x,y,marker='o',c='b',s=5) p.xlim(-2,2) p.ylim(-2,2) p.show() It's interesting to see what happens when you vary npts (from 50 to 1000). HTH, -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: Andrew S. <str...@as...> - 2005-10-15 00:28:04
|
Hi Jeff, This looks great but unfortunately I get the following error: astraw@aspiring:~/other-peoples-src/natgrid/example$ python example.py Traceback (most recent call last): File "example.py", line 3, in ? import nat File "/usr/lib/python2.3/site-packages/nat.py", line 362, in ? import string, math, sys, Numeric, cdms, MA, natgridmodule ImportError: No module named cdms So I modified nat.py in the following way, and it now works. And there was much rejoicing! -import string, math, sys, Numeric, cdms, MA, natgridmodule +import string, math, sys, Numeric, MA, natgridmodule Jeff Whitaker wrote: > Jesper Larsen wrote: > >> Hi matplotlib users, >> >> I have a long list of ungridded data that I would like to make a >> contour plot of. The data is simply a list of (longitude, latitude, >> datavalue) with the data value belonging the given longitude and >> latitude. As far as I understand contour() only accepts gridded data >> values. >> >> The solution is probably to interpolate the unstructured data to a >> regular grid and then plot the data. Has anyone tried doing that or >> know where to look for an interpolation/triangulation routine? >> >> Cheers, >> Jesper >> >> >> > > Jesper: Since this question has come up a couple of times, I decided to > cook up an example. First you'll need to download and install the > natgrid python module (included in CDAT, but I've separated it out from > the huge tarball and put it at > ftp://ftp.cdc.noaa.gov/Public/jsw/natgrid.tar.gz). Then try this: > > > from RandomArray import uniform > import pylab as p > import nat > > def griddata(x,y,z,xi,yi): > r = nat.Natgrid(y, x, yi, xi) > return r.rgrd(z) > > npts = 500 > x = uniform(-2,2,npts); y = uniform(-2,2,npts) > z = x*p.exp(-x**2-y**2) > > # x, y, and z are now vectors containing nonuniformly sampled data. > # Define a regular grid and grid data to it. > nx = 51; ny = 41 > x1 = p.linspace(-2,2,nx) > y1 = p.linspace(-2,2,ny) > xi, yi = p.meshgrid(x1, y1) > zi = griddata(x,y,z,x1,y1) > > # Contour the gridded data, plotting dots at the nonuniform data points. > CS = p.contour(xi,yi,zi,15,linewidths=0.5,colors=['k']) > CS = p.contourf(xi,yi,zi,15,cmap=p.cm.jet) > p.scatter(x,y,marker='o',c='b',s=5) > p.xlim(-2,2) > p.ylim(-2,2) > p.show() > > > > It's interesting to see what happens when you vary npts (from 50 to 1000). > > HTH, > > -Jeff > |
From: John H. <jdh...@ac...> - 2005-10-17 17:36:30
|
>>>>> "Andrew" == Andrew Straw <str...@as...> writes: Andrew> So I modified nat.py in the following way, and it now Andrew> works. And there was much rejoicing! Anyone want to volunteer for a wiki entry on this one? It comes up a lot... JDH |
From: Jeff W. <js...@fa...> - 2005-10-17 17:41:17
|
John Hunter wrote: >>>>>>"Andrew" == Andrew Straw <str...@as...> writes: >>>>>> >>>>>> > > Andrew> So I modified nat.py in the following way, and it now > Andrew> works. And there was much rejoicing! > >Anyone want to volunteer for a wiki entry on this one? It comes up a >lot... > >JDH > > John: I was thinking about putting together a natgrid toolbox, which would provide a function similar to matlab's griddata. This would building a new python interface to the natgrid c lib, since LLNL's license is too restrictive. The natgrid lib itself is GPL, which I think precludes it from being included in matplotlib proper. What do you think? -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: John H. <jdh...@ac...> - 2005-10-19 02:16:06
|
>>>>> "Jeff" == Jeff Whitaker <js...@fa...> writes: Jeff> John: I've now a got a toolkit built with no CDAT code in Jeff> it, using the NCAR natgrid library which is GPL. I've done a Jeff> fair amount of searching and haven't found anything else Jeff> that provides similar functionality with better Jeff> (i.e. BSD-like) licensing. The prototype natgrid toolkit is Jeff> at /Public/jsw/natgrid-0.1.tar.gz if you'd like to take a Jeff> look. All it does is provide a single function, griddata, Jeff> which works much the same as the matlab version. I'm ready Jeff> to put it CVS if you give the go ahead. I'm hesitant to include any GPL code even as a toolkit. For one thing, it decreases the impetus for someone to provide a version that is compatible with the mpl license. Perhaps this would be better placed on the wiki? I know that VTK is BSD compatible and has delaunay triangulation, but obviously it is impractical to try and pull anything out of VTK. I think the qhull license is less restrictive: http://www.qhull.org/COPYING.txt. In short, I wonder if we have really exhausted all the possibilities. Something from netlib? There was a recent thread on scipy in which Eric Jones posted a link to some code (FORTRAN I believe) that does something analogous. It would be nice to have something in C/C++ and something that is BSD compatible. Perhaps I'm dreaming. JDH |
From: Robert K. <rk...@uc...> - 2005-10-19 02:40:50
|
John Hunter wrote: >>>>>>"Jeff" == Jeff Whitaker <js...@fa...> writes: > > Jeff> John: I've now a got a toolkit built with no CDAT code in > Jeff> it, using the NCAR natgrid library which is GPL. I've done a > Jeff> fair amount of searching and haven't found anything else > Jeff> that provides similar functionality with better > Jeff> (i.e. BSD-like) licensing. The prototype natgrid toolkit is > Jeff> at /Public/jsw/natgrid-0.1.tar.gz if you'd like to take a > Jeff> look. All it does is provide a single function, griddata, > Jeff> which works much the same as the matlab version. I'm ready > Jeff> to put it CVS if you give the go ahead. > > I'm hesitant to include any GPL code even as a toolkit. For one > thing, it decreases the impetus for someone to provide a version that > is compatible with the mpl license. Perhaps this would be better > placed on the wiki? > > I know that VTK is BSD compatible and has delaunay triangulation, but > obviously it is impractical to try and pull anything out of VTK. I > think the qhull license is less restrictive: > http://www.qhull.org/COPYING.txt. In short, I wonder if we have > really exhausted all the possibilities. Something from netlib? > There was a recent thread on scipy in which Eric Jones posted a link > to some code (FORTRAN I believe) that does something analogous. It > would be nice to have something in C/C++ and something that is BSD > compatible. Perhaps I'm dreaming. I've spent time looking. Everything that I've found with a BSD-like license isn't a very good library. Global variables are usually the culprit. qhull, for example, is a real PITA in this regard. The code that Eric found was from ACM TOMS, I believe, and so I'd question its license. In any case, natgrid isn't Delaunay triangulation, but natural neighbors interpolation which is better (and probably state of the art for these kinds of graphics). It might be easiest to contact Dave Watson and ask if we can distribute his code in matplotlib under matplotlib's license. I can't find any contact information for him, however. -- Robert Kern rk...@uc... "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter |
From: John H. <jdh...@ac...> - 2005-10-19 02:53:16
|
>>>>> "Robert" == Robert Kern <rk...@uc...> writes: Robert> In any case, natgrid isn't Delaunay triangulation, but Robert> natural neighbors interpolation which is better (and Robert> probably state of the art for these kinds of graphics). It Robert> might be easiest to contact Dave Watson and ask if we can Robert> distribute his code in matplotlib under matplotlib's Robert> license. I can't find any contact information for him, Robert> however. I'm all for this but am not optimistic. It's my understanding that the NCAR folks are under a fairly heavy legal burden. Jeff: could you spearhead this effort and see if there is any interest on their part in relicensing their griddata code under a more permissive license? JDH |
From: Robert K. <rk...@uc...> - 2005-10-19 02:58:04
|
John Hunter wrote: >>>>>>"Robert" == Robert Kern <rk...@uc...> writes: > > Robert> In any case, natgrid isn't Delaunay triangulation, but > Robert> natural neighbors interpolation which is better (and > Robert> probably state of the art for these kinds of graphics). It > Robert> might be easiest to contact Dave Watson and ask if we can > Robert> distribute his code in matplotlib under matplotlib's > Robert> license. I can't find any contact information for him, > Robert> however. > > I'm all for this but am not optimistic. It's my understanding that > the NCAR folks are under a fairly heavy legal burden. Jeff: could you > spearhead this effort and see if there is any interest on their part > in relicensing their griddata code under a more permissive license? It's not NCAR's code, it's Dave Watson's. NCAR got permission to distribute the natgrid code under the GPL. We'd need to get independent permission from Dave Watson to distribute the code under the matplotlib license. -- Robert Kern rk...@uc... "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter |
From: Jeff W. <js...@fa...> - 2005-10-19 11:31:42
|
John Hunter wrote: >>>>>> "Robert" == Robert Kern <rk...@uc...> writes: >>>>>> > > Robert> In any case, natgrid isn't Delaunay triangulation, but > Robert> natural neighbors interpolation which is better (and > Robert> probably state of the art for these kinds of graphics). It > Robert> might be easiest to contact Dave Watson and ask if we can > Robert> distribute his code in matplotlib under matplotlib's > Robert> license. I can't find any contact information for him, > Robert> however. > > I'm all for this but am not optimistic. It's my understanding that > the NCAR folks are under a fairly heavy legal burden. Jeff: could you > spearhead this effort and see if there is any interest on their part > in relicensing their griddata code under a more permissive license? > > JDH > > John: I will do this and let you know. I agree with Robert on qhull - it's not the way to go. I did find this however: http://www.marine.csiro.au/~sakov/ Bivariate spline-based techniques offer robust and efficient approximation solutions. Here `csa' (standing for "cubic spline approximation") is a small library for approximating 2D irregular (scattered) data with bivariate C1-continuous cubic splines <http://www.math.uni-mannheim.de/%7Elsmath4/paper/VIS2001.pdf.gz>. For uniformly distributed data this algorithm is clearly superior than Natural Neighbours interpolation: it is faster (O(n)!), more robust (approximation, not interpolation) and better performing (C1!). (But take care when dealing with clustered data.) From version 1.09, `csa' can take advantage of the known variance of the data. The LICENSE reads: Bivariate Cubic Spline approximation library + standalone utility Version 1.14 Copyright 2002 CSIRO Marine Research GPO 1538 Hobart TAS 7001 Australia Please send comments and bugs to Pav...@cs... There is no warranty whatsoever. Use at your own risk. These code may be freely redistributed under the condition that the copyright notices are not removed. You may distribute modified versions of this code UNDER THE CONDITION THAT THIS CODE AND ANY MODIFICATIONS MADE TO IT IN THE SAME FILE REMAIN UNDER COPYRIGHT OF CSIRO, BOTH SOURCE AND OBJECT CODE ARE MADE FREELY AVAILABLE WITHOUT CHARGE, AND CLEAR NOTICE IS GIVEN OF THE MODIFICATIONS. If this sounds OK I'll investigate further. -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 NOAA/OAR/CDC R/CDC1 FAX : (303)497-6449 325 Broadway Web : http://www.cdc.noaa.gov/~jsw Boulder, CO, USA 80305-3328 Office: Skaggs Research Cntr 1D-124 |
From: Robert K. <rk...@uc...> - 2005-10-19 18:15:41
|
Jeff Whitaker wrote: > The LICENSE reads: > > Bivariate Cubic Spline approximation library + standalone utility > Version 1.14 > > Copyright 2002 CSIRO Marine Research > GPO 1538 Hobart > TAS 7001 > Australia > Please send comments and bugs to Pav...@cs... > > There is no warranty whatsoever. Use at your own risk. > > These code may be freely redistributed under the condition that the > copyright > notices are not removed. You may distribute modified versions of this code > UNDER THE CONDITION THAT THIS CODE AND ANY MODIFICATIONS MADE TO IT IN THE > SAME FILE REMAIN UNDER COPYRIGHT OF CSIRO, BOTH SOURCE AND OBJECT CODE ARE > MADE FREELY AVAILABLE WITHOUT CHARGE, AND CLEAR NOTICE IS GIVEN OF THE > MODIFICATIONS. > > If this sounds OK I'll investigate further. No, the CAPITALIZED part is very much not okay. It means we'd have to sign over the copyright to our modifications to CSIRO, and that the code can't be embedded in a commercial or proprietary project. -- Robert Kern rk...@uc... "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter |
From: Jeff W. <js...@fa...> - 2005-10-19 19:35:38
|
Robert Kern wrote: >Jeff Whitaker wrote: > > > >>The LICENSE reads: >> >>Bivariate Cubic Spline approximation library + standalone utility >>Version 1.14 >> >>Copyright 2002 CSIRO Marine Research >>GPO 1538 Hobart >>TAS 7001 >>Australia >>Please send comments and bugs to Pav...@cs... >> >>There is no warranty whatsoever. Use at your own risk. >> >>These code may be freely redistributed under the condition that the >>copyright >>notices are not removed. You may distribute modified versions of this code >>UNDER THE CONDITION THAT THIS CODE AND ANY MODIFICATIONS MADE TO IT IN THE >>SAME FILE REMAIN UNDER COPYRIGHT OF CSIRO, BOTH SOURCE AND OBJECT CODE ARE >>MADE FREELY AVAILABLE WITHOUT CHARGE, AND CLEAR NOTICE IS GIVEN OF THE >>MODIFICATIONS. >> >>If this sounds OK I'll investigate further. >> >> > >No, the CAPITALIZED part is very much not okay. It means we'd have to >sign over the copyright to our modifications to CSIRO, and that the code >can't be embedded in a commercial or proprietary project. > > > Oh well. I'm satisified then that there really isn't anything out there with acceptable license terms. I'm going to post my natgrid-based griddata module on the wiki and call it done (for now). -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: Alan I. <ai...@am...> - 2005-10-19 23:48:51
|
On Wed, 19 Oct 2005, Jeff Whitaker wrote: > Oh well. I'm satisified then that there really isn't anything out > there with acceptable license terms. I'm going to post my natgrid-based > griddata module on the wiki and call it done (for now). My view is that it is always worth asking for a different license before giving up. Many people choose licenses thoughtlessly. Some not, of course. Cheers, Alan Isaac PS I tried to find current contact info for the natgrid author and failed. |
From: Jeff W. <js...@fa...> - 2005-10-20 14:44:29
|
Robert Kern wrote: >Jeff Whitaker wrote: > > > >>The LICENSE reads: >> >>Bivariate Cubic Spline approximation library + standalone utility >>Version 1.14 >> >>Copyright 2002 CSIRO Marine Research >>GPO 1538 Hobart >>TAS 7001 >>Australia >>Please send comments and bugs to Pav...@cs... >> >>There is no warranty whatsoever. Use at your own risk. >> >>These code may be freely redistributed under the condition that the >>copyright >>notices are not removed. You may distribute modified versions of this code >>UNDER THE CONDITION THAT THIS CODE AND ANY MODIFICATIONS MADE TO IT IN THE >>SAME FILE REMAIN UNDER COPYRIGHT OF CSIRO, BOTH SOURCE AND OBJECT CODE ARE >>MADE FREELY AVAILABLE WITHOUT CHARGE, AND CLEAR NOTICE IS GIVEN OF THE >>MODIFICATIONS. >> >>If this sounds OK I'll investigate further. >> >> > >No, the CAPITALIZED part is very much not okay. It means we'd have to >sign over the copyright to our modifications to CSIRO, and that the code >can't be embedded in a commercial or proprietary project. > > > Robert: But this refers to modifications made to it "in the same file". The way I read this, if we don't change his source files we can redistribute them any way we want, as long as we leave the CSIRO copyright notices alone. -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: Chris B. <Chr...@no...> - 2005-10-20 16:17:26
|
Jeff Whitaker wrote: > Robert: But this refers to modifications made to it "in the same > file". The way I read this, if we don't change his source files we > can redistribute them any way we want, as long as we leave the CSIRO > copyright notices alone. I think Robert already answered this one: while we cold do that, we would then be distributing code with MPL that carried extra restrictions, so that MPL users couldn't modify it at will. I agree that this is to be avoided. Perhaps it's time to start a SciPy-extras collection that includes code under other, weird licenses. This would be SO much easier of people throwing their code out on the Internet would just use one of the common licensing schemes. I still think it's worth talking to the author, however. As Robert pointed out, these folks are clearly not all that cluefull about open source licenses. They may have little idea what they really are restricting. As a simple example, someone on the wxPython list has been developing a bunch of nifty higher-level widgets, hoping to get them included in the wxPython lib. However, he had released them all under the GPL, just because he didn't know any better. When someone wrote to him, pointing out that his stuff couldn't be used in any non-GPL projects, it turns out that wasn't his intent. I think he's going to re-release it all under the wxWidgets license (modified LGPL). However, it looks like this one may be standard CSIRO policy, so the author may have no choice, and changing an institutional policy is MUCH harder! Another, semi-related, thought: I feel strongly that MPL should focus on being a plotting library, NOT a full blown computational environment. That should be the focus of SciPy. Therefore, code to interpolate unstructured data would be better put into SciPy than MPL. Same licensing issues, of course. -Chris -- Christopher Barker, Ph.D. Oceanographer NOAA/OR&R/HAZMAT (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chr...@no... |
From: John H. <jdh...@ac...> - 2005-10-20 16:28:09
|
>>>>> "Chris" == Chris Barker <Chr...@no...> writes: Chris> I still think it's worth talking to the author, however. As I emailed him yesterday. No response yet though. Chris> Another, semi-related, thought: I feel strongly that MPL Chris> should focus on being a plotting library, NOT a full blown Chris> computational environment. That should be the focus of Chris> SciPy. Therefore, code to interpolate unstructured data Chris> would be better put into SciPy than MPL. Same licensing Chris> issues, of course. I think all of the mpl math/stats stuff will eventually end up in scipy as matplotlib becomes more tightly integrated with the new scipy. I've talked to Travis about that on a number of occasions and he is pulling some stuff out of mlab already. I think it is fine and good to put this kind of stuff into matplotlib in the meantime while we get the integration and installation issues sorted out. JDH |
From: Chris B. <Chr...@no...> - 2005-10-20 23:25:57
|
John Hunter wrote: > I think it is fine and good to put this kind of stuff into matplotlib > in the meantime while we get the integration and installation issues > sorted out. I agree. It's certainly good that there is a home for it somewhere! I'm glad to hear that you do have better matplotlib-Scipy integration in mind....things are really looking up! -Chris -- Christopher Barker, Ph.D. Oceanographer NOAA/OR&R/HAZMAT (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chr...@no... |
From: Andrea R. <ari...@pi...> - 2005-10-21 09:05:58
|
Hi all, I'm an absolute lurker here, so forgive me if my suggestions are useless. Anyway, some time ago I've found this library <http:// gts.sourceforge.net/> that could be of some help. Or perhaps it's a complete different beast and I'm out of the way to go... HTH, Andrea |
From: Jeff W. <js...@fa...> - 2005-10-21 11:05:29
|
Andrea Riciputi wrote: > Hi all, > I'm an absolute lurker here, so forgive me if my suggestions are > useless. Anyway, some time ago I've found this library > <http://gts.sourceforge.net/> that could be of some help. Or perhaps > it's a complete different beast and I'm out of the way to go... > > HTH, > Andrea > Andrea: There are lots of things that would work well - but the licensing is a problem. GTS is GPL, we need something with a less restrictive license (more like Python's). -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/CDC R/CDC1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-124 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg |
From: Chris B. <Chr...@no...> - 2005-10-21 16:32:54
|
Jeff Whitaker wrote: > Andrea: There are lots of things that would work well - but the > licensing is a problem. GTS is GPL, we need something with a less > restrictive license (more like Python's). No, it's LGPL, which is much better, but maybe still not OK for mpl. I guess the problem is that mpl is kind of a library of libraries, rather than an application, so it would be awkward to have mixed licenses in it. -Chris -- Christopher Barker, Ph.D. Oceanographer NOAA/OR&R/HAZMAT (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chr...@no... |
From: Andrea R. <ari...@pi...> - 2005-10-22 02:11:03
|
On Oct 21, 2005, at 18:32 , Chris Barker wrote: > Jeff Whitaker wrote: > >> Andrea: There are lots of things that would work well - but the >> licensing is a problem. GTS is GPL, we need something with a less >> restrictive license (more like Python's). >> > > No, it's LGPL, which is much better, but maybe still not OK for > mpl. I guess the problem is that mpl is kind of a library of > libraries, rather than an application, so it would be awkward to > have mixed licenses in it. > > -Chris I suggested GTS exactly because I remembered that it is LGPL, and I thought it would had been ok for your needs. But I must admit that I know very little about licences. Andrea |
From: Andrea G. <and...@ti...> - 2005-10-20 21:40:33
|
Hello NG, > I still think it's worth talking to the author, however. As Robert > pointed out, these folks are clearly not all that cluefull about open > source licenses. They may have little idea what they really are > restricting. As a simple example, someone on the wxPython list has been > developing a bunch of nifty higher-level widgets, hoping to get them > included in the wxPython lib. However, he had released them all under > the GPL, just because he didn't know any better. When someone wrote to > him, pointing out that his stuff couldn't be used in any non-GPL > projects, it turns out that wasn't his intent. Yeah, that's me ;-) It was not my intent because I am not really interested in licensing things... I never cared about them, and I used the GPL only because it was the first thing that came into my mind ;-) Big mistake. > I think he's going to > re-release it all under the wxWidgets license (modified LGPL). It's done... I have changed all the widgets license to the standard wxWidgets license. I hope this will work. If it is good enough for wxPython, so it is for me. Andrea. "Imagination Is The Only Weapon In The War Against Reality." http://xoomer.virgilio.it/infinity77 |
From: Chris B. <Chr...@no...> - 2005-10-19 05:43:52
|
Robert Kern wrote: > qhull, for example, is a real PITA in this regard. Darn, it looked pretty promising from the web site. > In any case, natgrid isn't Delaunay triangulation, but natural neighbors > interpolation which is better (and probably state of the art for these > kinds of graphics). Although there are other uses for delaunay triangulization, so it would be nice to have a python lib that does it well. What about Jonathan Shewchuk's Triangle? I don't know how clean the code is but it's fast and powerful. As for license: """ Please note that although Triangle is freely available, it is copyrighted by the author and may not be sold or included in commercial products without a license. """ I wish he'd just a pick a license and be done with it, but given that Python. MPL, and SciPy are not commercial, he'd probably be OK with it. -Chris -- Christopher Barker, Ph.D. Oceanographer NOAA/OR&R/HAZMAT (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chr...@no... |
From: Robert K. <rk...@uc...> - 2005-10-19 05:59:28
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Chris Barker wrote: > Robert Kern wrote: > >> qhull, for example, is a real PITA in this regard. > > Darn, it looked pretty promising from the web site. It's not. It's well-known to be a bad library. There's a Python interface to qhull, but it uses pipes to communicate with a separate qhull process. >> In any case, natgrid isn't Delaunay triangulation, but natural neighbors >> interpolation which is better (and probably state of the art for these >> kinds of graphics). > > Although there are other uses for delaunay triangulization, so it would > be nice to have a python lib that does it well. > > What about Jonathan Shewchuk's Triangle? I don't know how clean the code > is but it's fast and powerful. As for license: > > """ > Please note that although Triangle is freely available, it is > copyrighted by the author and may not be sold or included in commercial > products without a license. > """ > > I wish he'd just a pick a license and be done with it, but given that > Python. MPL, and SciPy are not commercial, he'd probably be OK with it. MPL and Scipy won't take code that can't be redistributed commercially (much less proprietarily). There's no indication that Shewchuk will allow that. -- Robert Kern rk...@uc... "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter |