Re: [Matplotlib-users] luminocity plot on hammer projection
imshow always assumes a regular rectangular grid of pixels. To plot image data on a non-rectilinear projection, you need to use pcolor or pcolormesh. You may also want to look at the basemap toolkit, which provides much better support for geographic projections. The ones included in matplotlib are essentially "toy" examples to test the infrastructure, but aren't really intended for advanced usage. Cheers, Mike dasratsel wrote: > Hi, > > I've done some poking an I can't find a way to use imshow() to plot a > luminosity map on a hammer projection. (looking to generate a plot like > http://en.wikipedia.org/wiki/Image:WMAP_2008.png). Just setting the > projection in a call to subplot gives some axes and an off-center retangular > image of my array. Bearing in mind that I am completely new to matplotlib, > does anyone have an idea of how to get this sort of plot? > > Thanks, > Kris > > (PS. Apologies if this shows up in two places, I'm not used to using mailing > lists) > -- Michael Droettboom Science Software Branch Operations and Engineering Division Space Telescope Science Institute Operated by AURA for NASA - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] luminocity plot on hammer projection
Eric Firing wrote: > dasratsel wrote: > >> Hi, >> >> I've done some poking an I can't find a way to use imshow() to plot a >> luminosity map on a hammer projection. (looking to generate a plot like >> http://en.wikipedia.org/wiki/Image:WMAP_2008.png). Just setting the >> projection in a call to subplot gives some axes and an off-center retangular >> image of my array. Bearing in mind that I am completely new to matplotlib, >> does anyone have an idea of how to get this sort of plot? >> >> Thanks, >> Kris >> >> (PS. Apologies if this shows up in two places, I'm not used to using mailing >> lists) >> > > Kris, > > For any sort of mapping like this, you will probably want to use basemap > matplotlib toolkit, except that I don't see "hammer" among the supported > projections. > > With straight mpl, imshow does not support projections. You could use > pcolor (very slow) or pcolormesh. In neither case will you get > interpolation; you will be specifying colored quadrilaterals. > > Eric > > > Kris: Basemap does not support the 'hammer' projection, but it does have mollweide, which is very similar. Something like this ought to do it: from mpl_toolkits.basemap import Basemap import matplotlib.pyplot as plt # lon_0 is the center longitude of the data. map = Basemap(projection='moll',lon_0=180) # lons, lats are the longitudes and latitudes of the data # lons.shape, lats.shape = data.shape x, y = map(lons,lats) # make a filled mesh plot. im = map.pcolormesh(x,y,data,cmap=plt.cm.jet) # draw a boundary around the map map.drawmapboundary() plt.show() -Jeff -- Jeffrey S. Whitaker Phone : (303)497-6313 NOAA/OAR/CDC R/PSD1FAX : (303)497-6449 325 BroadwayBoulder, CO, USA 80305-3328 - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] luminocity plot on hammer projection
dasratsel wrote: > Hi, > > I've done some poking an I can't find a way to use imshow() to plot a > luminosity map on a hammer projection. (looking to generate a plot like > http://en.wikipedia.org/wiki/Image:WMAP_2008.png). Just setting the > projection in a call to subplot gives some axes and an off-center retangular > image of my array. Bearing in mind that I am completely new to matplotlib, > does anyone have an idea of how to get this sort of plot? > > Thanks, > Kris > > (PS. Apologies if this shows up in two places, I'm not used to using mailing > lists) Kris, For any sort of mapping like this, you will probably want to use basemap matplotlib toolkit, except that I don't see "hammer" among the supported projections. With straight mpl, imshow does not support projections. You could use pcolor (very slow) or pcolormesh. In neither case will you get interpolation; you will be specifying colored quadrilaterals. Eric - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] luminocity plot on hammer projection
Hi, I've done some poking an I can't find a way to use imshow() to plot a luminosity map on a hammer projection. (looking to generate a plot like http://en.wikipedia.org/wiki/Image:WMAP_2008.png). Just setting the projection in a call to subplot gives some axes and an off-center retangular image of my array. Bearing in mind that I am completely new to matplotlib, does anyone have an idea of how to get this sort of plot? Thanks, Kris (PS. Apologies if this shows up in two places, I'm not used to using mailing lists) -- View this message in context: http://www.nabble.com/luminocity-plot-on-hammer-projection-tp19829899p19829899.html Sent from the matplotlib - users mailing list archive at Nabble.com. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
