missing projections

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 : Jeffrey.S.Whitaker@...236...
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 : Jeffrey.S.Whitaker@...236...
325 Broadway Office : Skaggs Research Cntr 1D-113
Boulder, CO, USA 80303-3328 Web : http://tinyurl.com/5telg