Basemap offers many projections, but is missing two of the most useful ones: - For satellite applications, it would be helpful to have a "camera" projection, i.e., a projection that shows the Earth as viewed from a specified point in space. This would be a generalization of the current geostationary projection. - Basemap current offers North-Polar and South-Polar azimuthal equidistant projections. A useful generalization is the azimuthal equidistant projection with a specified latitude and longitude at the center of the map. -- View this message in context: http://old.nabble.com/missing-projections-tp27297141p27297141.html Sent from the matplotlib - devel mailing list archive at Nabble.com.
If and when you have time on your hands, a projection that is rarely used but quite interesting is Guyou's Doubly-Periodic Projection. (See the first and third figures in http://www.members.shaw.ca/quadibloc/maps/mcf0703.htm). This projection puts the worst distortion at four points in the ocean, and does a reasonable job of preserving the shapes and relative sizes of the major land masses. -- View this message in context: http://old.nabble.com/missing-projections-tp27297141p27297216.html Sent from the matplotlib - devel mailing list archive at Nabble.com.
Dr. Phillip M. Feldman wrote: > Basemap offers many projections, but is missing two of the most useful ones: > > - For satellite applications, it would be helpful to have a "camera" > projection, i.e., a projection that shows the Earth as viewed from a > specified point in space. This would be a generalization of the current > geostationary projection. > Philip: Don't think the proj4 lib supports this. > - Basemap current offers North-Polar and South-Polar azimuthal equidistant > projections. A useful generalization is the azimuthal equidistant > projection with a specified latitude and longitude at the center of the map. > That's already implemented - just use the 'aeqd' projection, specifying lat_0,lon_0,width and height keywords. -Jeff
Jeff Whitaker wrote: > Dr. Phillip M. Feldman wrote: > >> Basemap offers many projections, but is missing two of the most useful ones: >> >> - For satellite applications, it would be helpful to have a "camera" >> projection, i.e., a projection that shows the Earth as viewed from a >> specified point in space. This would be a generalization of the current >> geostationary projection. >> >> > > Philip: Don't think the proj4 lib supports this. > I think it's already in there -- see nsper, for near sided perspective. -Andrew
Andrew Straw wrote: > Jeff Whitaker wrote: > >> Dr. Phillip M. Feldman wrote: >> >> >>> Basemap offers many projections, but is missing two of the most useful ones: >>> >>> - For satellite applications, it would be helpful to have a "camera" >>> projection, i.e., a projection that shows the Earth as viewed from a >>> specified point in space. This would be a generalization of the current >>> geostationary projection. >>> >>> >>> >> Philip: Don't think the proj4 lib supports this. >> >> > I think it's already in there -- see nsper, for near sided perspective. > > -Andrew > > Hello Andrew- It does sound as thought nsper is exactly what I need, but when I try to use it, I get the following error message: ValueError: 'nsper' is an unsupported projection. The supported projections are: aeqd Azimuthal Equidistant poly Polyconic gnom Gnomonic moll Mollweide tmerc Transverse Mercator nplaea North-Polar Lambert Azimuthal gall Gall Stereographic Cylindrical mill Miller Cylindrical merc Mercator stere Stereographic npstere North-Polar Stereographic geos Geostationary vandg van der Grinten laea Lambert Azimuthal Equal Area mbtfpq McBryde-Thomas Flat-Polar Quartic sinu Sinusoidal spstere South-Polar Stereographic lcc Lambert Conformal npaeqd North-Polar Azimuthal Equidistant eqdc Equidistant Conic cyl Cylindrical Equidistant omerc Oblique Mercator aea Albers Equal Area spaeqd South-Polar Azimuthal Equidistant ortho Orthographic cass Cassini-Soldner splaea South-Polar Lambert Azimuthal robin Robinson Phillip
Phillip M. Feldman wrote: > Andrew Straw wrote: >> Jeff Whitaker wrote: >> >>> Dr. Phillip M. Feldman wrote: >>> >>>> Basemap offers many projections, but is missing two of the most >>>> useful ones: >>>> >>>> - For satellite applications, it would be helpful to have a "camera" >>>> projection, i.e., a projection that shows the Earth as viewed from a >>>> specified point in space. This would be a generalization of the >>>> current >>>> geostationary projection. >>>> >>> Philip: Don't think the proj4 lib supports this. >>> >> I think it's already in there -- see nsper, for near sided perspective. >> >> -Andrew >> >> > Hello Andrew- > > It does sound as thought nsper is exactly what I need, but when I try > to use it, I get the following error message: > > ValueError: 'nsper' is an unsupported projection. > The supported projections are: > > aeqd Azimuthal Equidistant > poly Polyconic > gnom Gnomonic > moll Mollweide > tmerc Transverse Mercator > nplaea North-Polar Lambert Azimuthal > gall Gall Stereographic Cylindrical > mill Miller Cylindrical > merc Mercator > stere Stereographic > npstere North-Polar Stereographic > geos Geostationary > vandg van der Grinten > laea Lambert Azimuthal Equal Area > mbtfpq McBryde-Thomas Flat-Polar Quartic > sinu Sinusoidal > spstere South-Polar Stereographic > lcc Lambert Conformal > npaeqd North-Polar Azimuthal Equidistant > eqdc Equidistant Conic > cyl Cylindrical Equidistant > omerc Oblique Mercator > aea Albers Equal Area > spaeqd South-Polar Azimuthal Equidistant > ortho Orthographic > cass Cassini-Soldner > splaea South-Polar Lambert Azimuthal > robin Robinson > > Phillip Philip: I think Andrew meant nsper is in proj4. I'll look into adding support for it in Basemap. -Jeff
Phillip M. Feldman wrote: > Jeff Whitaker wrote: >> Phillip M. Feldman wrote: >>> Andrew Straw wrote: >>>> Jeff Whitaker wrote: >>>> >>>>> Dr. Phillip M. Feldman wrote: >>>>> >>>>>> Basemap offers many projections, but is missing two of the most >>>>>> useful ones: >>>>>> >>>>>> - For satellite applications, it would be helpful to have a "camera" >>>>>> projection, i.e., a projection that shows the Earth as viewed from a >>>>>> specified point in space. This would be a generalization of the >>>>>> current >>>>>> geostationary projection. >>>>>> >>>>> Philip: Don't think the proj4 lib supports this. >>>>> >>>> I think it's already in there -- see nsper, for near sided >>>> perspective. >>>> >>>> -Andrew >>>> Philip: I've added the near-sided perspective projection to basemap svn - see the nsper_demo.py example. It only works if the earth is assumed to be a perfect sphere (no ellipsoids allowed). -Jeff >>>> >>> Hello Andrew- >>> >>> It does sound as thought nsper is exactly what I need, but when I >>> try to use it, I get the following error message: >>> >>> ValueError: 'nsper' is an unsupported projection. >>> The supported projections are: >>> >>> aeqd Azimuthal Equidistant >>> poly Polyconic >>> gnom Gnomonic >>> moll Mollweide >>> tmerc Transverse Mercator >>> nplaea North-Polar Lambert Azimuthal >>> gall Gall Stereographic Cylindrical >>> mill Miller Cylindrical >>> merc Mercator >>> stere Stereographic >>> npstere North-Polar Stereographic >>> geos Geostationary >>> vandg van der Grinten >>> laea Lambert Azimuthal Equal Area >>> mbtfpq McBryde-Thomas Flat-Polar Quartic >>> sinu Sinusoidal >>> spstere South-Polar Stereographic >>> lcc Lambert Conformal >>> npaeqd North-Polar Azimuthal Equidistant >>> eqdc Equidistant Conic >>> cyl Cylindrical Equidistant >>> omerc Oblique Mercator >>> aea Albers Equal Area >>> spaeqd South-Polar Azimuthal Equidistant >>> ortho Orthographic >>> cass Cassini-Soldner >>> splaea South-Polar Lambert Azimuthal >>> robin Robinson >>> >>> Phillip >> Philip: I think Andrew meant nsper is in proj4. I'll look into >> adding support for it in Basemap. >> >> -Jeff >> > Thanks! -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/PSD R/PSD1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-113 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg
This sounds great. Thanks! So far I haven't figured out how to use it. I downloaded the matplotlib SVN and installed it, but was not able to find "nsper_demo.py". Phillip Jeff Whitaker wrote: > Phillip M. Feldman wrote: >> Jeff Whitaker wrote: >>> Phillip M. Feldman wrote: >>>> Andrew Straw wrote: >>>>> Jeff Whitaker wrote: >>>>> >>>>>> Dr. Phillip M. Feldman wrote: >>>>>> >>>>>>> Basemap offers many projections, but is missing two of the most >>>>>>> useful ones: >>>>>>> >>>>>>> - For satellite applications, it would be helpful to have a >>>>>>> "camera" >>>>>>> projection, i.e., a projection that shows the Earth as viewed >>>>>>> from a >>>>>>> specified point in space. This would be a generalization of the >>>>>>> current >>>>>>> geostationary projection. >>>>>>> >>>>>> Philip: Don't think the proj4 lib supports this. >>>>>> >>>>> I think it's already in there -- see nsper, for near sided >>>>> perspective. >>>>> >>>>> -Andrew >>>>> > > Philip: I've added the near-sided perspective projection to basemap > svn - see the nsper_demo.py example. It only works if the earth is > assumed to be a perfect sphere (no ellipsoids allowed). > > -Jeff >>>>> >>>> Hello Andrew- >>>> >>>> It does sound as thought nsper is exactly what I need, but when I >>>> try to use it, I get the following error message: >>>> >>>> ValueError: 'nsper' is an unsupported projection. >>>> The supported projections are: >>>> >>>> aeqd Azimuthal Equidistant >>>> poly Polyconic >>>> gnom Gnomonic >>>> moll Mollweide >>>> tmerc Transverse Mercator >>>> nplaea North-Polar Lambert Azimuthal >>>> gall Gall Stereographic Cylindrical >>>> mill Miller Cylindrical >>>> merc Mercator >>>> stere Stereographic >>>> npstere North-Polar Stereographic >>>> geos Geostationary >>>> vandg van der Grinten >>>> laea Lambert Azimuthal Equal Area >>>> mbtfpq McBryde-Thomas Flat-Polar Quartic >>>> sinu Sinusoidal >>>> spstere South-Polar Stereographic >>>> lcc Lambert Conformal >>>> npaeqd North-Polar Azimuthal Equidistant >>>> eqdc Equidistant Conic >>>> cyl Cylindrical Equidistant >>>> omerc Oblique Mercator >>>> aea Albers Equal Area >>>> spaeqd South-Polar Azimuthal Equidistant >>>> ortho Orthographic >>>> cass Cassini-Soldner >>>> splaea South-Polar Lambert Azimuthal >>>> robin Robinson >>>> >>>> Phillip >>> Philip: I think Andrew meant nsper is in proj4. I'll look into >>> adding support for it in Basemap. >>> >>> -Jeff >>> >> Thanks! > >
Phillip M. Feldman wrote: > This sounds great. Thanks! > > So far I haven't figured out how to use it. I downloaded the > matplotlib SVN and installed it, but was not able to find > "nsper_demo.py". > > Phillip Phillip: Basemap is a separate toolkit, you won't get it from the matplotlib svn trunk. Instead of svn co https://matplotlib.svn.sourceforge.net/svnroot/matplotlib/trunk/matplotlib matplotlib do svn co https://matplotlib.svn.sourceforge.net/svnroot/matplotlib/trunk/toolkits/basemap basemap -Jeff > > Jeff Whitaker wrote: >> Phillip M. Feldman wrote: >>> Jeff Whitaker wrote: >>>> Phillip M. Feldman wrote: >>>>> Andrew Straw wrote: >>>>>> Jeff Whitaker wrote: >>>>>> >>>>>>> Dr. Phillip M. Feldman wrote: >>>>>>> >>>>>>>> Basemap offers many projections, but is missing two of the most >>>>>>>> useful ones: >>>>>>>> >>>>>>>> - For satellite applications, it would be helpful to have a >>>>>>>> "camera" >>>>>>>> projection, i.e., a projection that shows the Earth as viewed >>>>>>>> from a >>>>>>>> specified point in space. This would be a generalization of >>>>>>>> the current >>>>>>>> geostationary projection. >>>>>>>> >>>>>>> Philip: Don't think the proj4 lib supports this. >>>>>>> >>>>>> I think it's already in there -- see nsper, for near sided >>>>>> perspective. >>>>>> >>>>>> -Andrew >>>>>> >> >> Philip: I've added the near-sided perspective projection to basemap >> svn - see the nsper_demo.py example. It only works if the earth is >> assumed to be a perfect sphere (no ellipsoids allowed). >> >> -Jeff >>>>>> >>>>> Hello Andrew- >>>>> >>>>> It does sound as thought nsper is exactly what I need, but when I >>>>> try to use it, I get the following error message: >>>>> >>>>> ValueError: 'nsper' is an unsupported projection. >>>>> The supported projections are: >>>>> >>>>> aeqd Azimuthal Equidistant >>>>> poly Polyconic >>>>> gnom Gnomonic >>>>> moll Mollweide >>>>> tmerc Transverse Mercator >>>>> nplaea North-Polar Lambert Azimuthal >>>>> gall Gall Stereographic Cylindrical >>>>> mill Miller Cylindrical >>>>> merc Mercator >>>>> stere Stereographic >>>>> npstere North-Polar Stereographic >>>>> geos Geostationary >>>>> vandg van der Grinten >>>>> laea Lambert Azimuthal Equal Area >>>>> mbtfpq McBryde-Thomas Flat-Polar Quartic >>>>> sinu Sinusoidal >>>>> spstere South-Polar Stereographic >>>>> lcc Lambert Conformal >>>>> npaeqd North-Polar Azimuthal Equidistant >>>>> eqdc Equidistant Conic >>>>> cyl Cylindrical Equidistant >>>>> omerc Oblique Mercator >>>>> aea Albers Equal Area >>>>> spaeqd South-Polar Azimuthal Equidistant >>>>> ortho Orthographic >>>>> cass Cassini-Soldner >>>>> splaea South-Polar Lambert Azimuthal >>>>> robin Robinson >>>>> >>>>> Phillip >>>> Philip: I think Andrew meant nsper is in proj4. I'll look into >>>> adding support for it in Basemap. >>>> >>>> -Jeff >>>> >>> Thanks! >> >> > -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX : (303)497-6449 NOAA/OAR/PSD R/PSD1 Email : Jef...@no... 325 Broadway Office : Skaggs Research Cntr 1D-113 Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg