[matplotlib-devel] missing projections
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. -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] missing projections
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. -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] missing projections
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 -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] [Matplotlib-users] strange error when attempting to generate a map using 'geos' projection
Jeff Whitaker wrote: > Dr. Phillip M. Feldman wrote: >> Jeff Whitaker wrote: >> >>> >>> Philip: That's an error from the proj4 c library saying that it >>> didn't like one of the parameters you used to define the >>> projection. Since you didn't include the parameters you used, I >>> can't say which one is the culprit. >>> >>> -Jeff >>> >>> >> >> > Philip: I believe that lat_0 must be zero for the geostationary > projection (you have to be looking down on the equator). I usually > leave the lat_0 parameter off entirely, in which case zero is > assumed. I'll try to catch that and raise a more insightful error > message. > > -Jeff > Hm. I suppose that you are right. "Geostationary" does imply that the viewer is 35786.2 km above the equator. What would be more useful is a geosynchronous projection. This would allow the viewer to be located at any latitude. Geostationary is a special case of geosynchronous. Even more useful than a geosynchronous projection is a camera projection that allows one to place the viewer at any location in space (i.e., any latitude and longitude for the nadir point, and any altitude). (I wrote something like this is Fortran 25 years ago). Generalizing the existing geostationary projection to turn it into a camera projection would make it far more useful. I hope that someone will consider making this change. Phillip -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] missing projections
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 -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] [Matplotlib-users] strange error when attempting to generate a map using 'geos' projection
On 2010-01-24 21:17 , Phillip M. Feldman wrote: > Even more useful than a geosynchronous projection is a camera projection > that allows one to place the viewer at any location in space (i.e., any > latitude and longitude for the nadir point, and any altitude). (I wrote > something like this is Fortran 25 years ago). Generalizing the existing > geostationary projection to turn it into a camera projection would make > it far more useful. I hope that someone will consider making this change. The projection code is not written by the basemap team. Rather, it uses the PROJ.4 library. You may direct feature requests for the PROJ.4 library here: http://trac.osgeo.org/proj/ -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
Re: [matplotlib-devel] missing projections
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 tmercTransverse Mercator nplaea North-Polar Lambert Azimuthal gall Gall Stereographic Cylindrical mill Miller Cylindrical merc Mercator stereStereographic npstere North-Polar Stereographic geos Geostationary vandgvan 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 omercOblique Mercator aea Albers Equal Area spaeqd South-Polar Azimuthal Equidistant orthoOrthographic cass Cassini-Soldner splaea South-Polar Lambert Azimuthal robinRobinson Phillip -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
[matplotlib-devel] with projection=aeqd, width has no effect
When I generate a map with the aeqd projection, the width parameter has no effect. This looks like a bug. -- View this message in context: http://old.nabble.com/with-projection%3Daeqd%2C-width-has-no-effect-tp27302405p27302405.html Sent from the matplotlib - devel mailing list archive at Nabble.com. -- Throughout its 18-year history, RSA Conference consistently attracts the world's best and brightest in the field, creating opportunities for Conference attendees to learn about information security's most important issues through interactions with peers, luminaries and emerging and established companies. http://p.sf.net/sfu/rsaconf-dev2dev ___ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
