Hello, I'm creating a web application that will take user input from a javascript map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, llcrnrlat, llcrnrlon) and possibly a switch for polar projection. Other than that I have no further information. Which projection is the most suitable to handle anything from a 'global' plot to a zoom say over a state? I don't see the zoom being too tight, but global projections are likely. I personally prefer Equal Area, hence right now I'm working with 'aeqd', but I seem to have problems if the plot is global with that projection. Just looking for advice, opinions, and ideally examples if anyone has created a similar function / module to use in a web environment. Thanks! -john -- View this message in context: http://www.nabble.com/dynamic-basemap-tp20121594p20121594.html Sent from the matplotlib - users mailing list archive at Nabble.com.
John [H2O] wrote:
> Hello,
>
> I'm creating a web application that will take user input from a javascript
> map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, llcrnrlat,
> llcrnrlon) and possibly a switch for polar projection. Other than that I
> have no further information. Which projection is the most suitable to handle
> anything from a 'global' plot to a zoom say over a state? I don't see the
> zoom being too tight, but global projections are likely. I personally prefer
> Equal Area, hence right now I'm working with 'aeqd', but I seem to have
> problems if the plot is global with that projection.
>
> Just looking for advice, opinions, and ideally examples if anyone has
> created a similar function / module to use in a web environment.
>
> Thanks!
> -john
>
John: Sounds like you need one of the global cylindrical projections,
such as cylindrical equidistant ('cyl'), miller ('mill') or mercator
('merc'). In the svn version, you also have Gall Stereographic
('gall'). See
http://matplotlib.sourceforge.net/basemap/doc/html/users/mapsetup.html
for examples. Unfortunately, none of them are equal-area. Mollweide
('moll') is a global equal-area projection, but it's only global (you
can't specify a domain that isn't global). For the polar option, I
suggest polar lambert azimuthal equal-area
(http://matplotlib.sourceforge.net/basemap/doc/html/users/plaea.html).
The user can specify whether he/she wants the south or north polar
aspect, and the latitude of the outer edge.
-Jeff
--
Jeffrey S. Whitaker Phone : (303)497-6313
NOAA/OAR/CDC R/PSD1 FAX : (303)497-6449
325 Broadway Boulder, CO, USA 80305-3328
Hi, I think I am running into the same thing John is here. When you want to display the whole earth in 'aeqd' mode, the projection needs to be onto a circle. As it is, what is plotted is a square that just fits inside the circle I want. Here is a link to a photo of the kind of projection I want. http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif Is there a way to get the whole earth plotted with 'aeqd'? Thanks, Rob John [H2O] wrote: > > Hello, > > I'm creating a web application that will take user input from a javascript > map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, llcrnrlat, > llcrnrlon) and possibly a switch for polar projection. Other than that I > have no further information. Which projection is the most suitable to > handle anything from a 'global' plot to a zoom say over a state? I don't > see the zoom being too tight, but global projections are likely. I > personally prefer Equal Area, hence right now I'm working with 'aeqd', but > I seem to have problems if the plot is global with that projection. > > Just looking for advice, opinions, and ideally examples if anyone has > created a similar function / module to use in a web environment. > > Thanks! > -john > -- View this message in context: http://www.nabble.com/dynamic-basemap-tp20121594p21223766.html Sent from the matplotlib - users mailing list archive at Nabble.com.
I just thought I would include some code so you can see what I mean. from mpl_toolkits.basemap import Basemap import matplotlib.pyplot as plt import numpy as np map=Basemap(projection='aeqd', lat_0=46, lon_0=-118.4, width=28300000, height=28300000, resolution='c', area_thresh=1000.) map.drawcoastlines() map.drawcountries() map.fillcontinents(color='coral') map.drawmapboundary() plt.show() Rob Frohne wrote: > > Hi, > > I think I am running into the same thing John is here. When you want to > display the whole earth in 'aeqd' mode, the projection needs to be onto a > circle. As it is, what is plotted is a square that just fits inside the > circle I want. Here is a link to a photo of the kind of projection I > want. > > http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif > > Is there a way to get the whole earth plotted with 'aeqd'? > > Thanks, > > Rob > > > John [H2O] wrote: >> >> Hello, >> >> I'm creating a web application that will take user input from a >> javascript map to give me bounding coordinates (i.e. urcrnrlat, >> urcrnrlon, llcrnrlat, llcrnrlon) and possibly a switch for polar >> projection. Other than that I have no further information. Which >> projection is the most suitable to handle anything from a 'global' plot >> to a zoom say over a state? I don't see the zoom being too tight, but >> global projections are likely. I personally prefer Equal Area, hence >> right now I'm working with 'aeqd', but I seem to have problems if the >> plot is global with that projection. >> >> Just looking for advice, opinions, and ideally examples if anyone has >> created a similar function / module to use in a web environment. >> >> Thanks! >> -john >> > > -- View this message in context: http://www.nabble.com/dynamic-basemap-tp20121594p21223795.html Sent from the matplotlib - users mailing list archive at Nabble.com.
Rob Frohne wrote: > Hi, > > I think I am running into the same thing John is here. When you want to > display the whole earth in 'aeqd' mode, the projection needs to be onto a > circle. As it is, what is plotted is a square that just fits inside the > circle I want. Here is a link to a photo of the kind of projection I want. > > http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif > > Is there a way to get the whole earth plotted with 'aeqd'? > Rob: No, you can't get the whole earth - the most you can get is the cube that fits within it. I can look into adding that functionality for the aeqd projection if there's a real use case. Note that there are other whole-earth projections available (mollweide, vandergrinten, robinson, sinuisoidal etc). These projections have much less distortion far away from the center of the map than the azimuthal equidistant does. Why do you want to use aeqd to plot the whole globe? -Jeff > Thanks, > > Rob > > > John [H2O] wrote: > >> Hello, >> >> I'm creating a web application that will take user input from a javascript >> map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, llcrnrlat, >> llcrnrlon) and possibly a switch for polar projection. Other than that I >> have no further information. Which projection is the most suitable to >> handle anything from a 'global' plot to a zoom say over a state? I don't >> see the zoom being too tight, but global projections are likely. I >> personally prefer Equal Area, hence right now I'm working with 'aeqd', but >> I seem to have problems if the plot is global with that projection. >> >> Just looking for advice, opinions, and ideally examples if anyone has >> created a similar function / module to use in a web environment. >> >> Thanks! >> -john >> >> > > -- 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
Rob Frohne wrote: > Hi Jeff, > > I am an amateur radio operator, and I am writing a little application to > display where the major lobe of my antenna is pointing. I can control the > direction of my antenna with the computer, and it would be nice to have a > display of the whole world, as well as circles representing how far the > station I am talking to is, and radial lines showing the bearings. I'd like > to show the bearings along the edge of the map. For this type of map, a > circle is a much better boundary than a square, but if it has to be a > square, we should be able to make it a square bounding the circle, not the > other way around. I think I can even plot the station's location given data > I get from the Internet using this software. I am just learning Python, but > it appears to be ideal for what I'm doing. > > Right now I'm trying to figure out how to get the Eclipse IDE I am trying > out to show me the source code for Basemap. :-) > > Thanks for the expert help! > > Rob > Rob: I've updated basemap in SVN so that if neither a width/height or corner lat/lons are provided, the whole world is plotted in a circle with projection='aeqd'. If you can access SVN please try it out and let me know how it works for you. If not, I can provide you with a tarball. The full-disk aeqd will not work right now with ellipsoids, only for perfect spheres. Is that a problem for you? -Jeff > Jeff Whitaker wrote: > >> Rob Frohne wrote: >> >>> Hi, >>> >>> I think I am running into the same thing John is here. When you want to >>> display the whole earth in 'aeqd' mode, the projection needs to be onto a >>> circle. As it is, what is plotted is a square that just fits inside the >>> circle I want. Here is a link to a photo of the kind of projection I >>> want. >>> >>> http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif >>> >>> Is there a way to get the whole earth plotted with 'aeqd'? >>> >>> >> Rob: No, you can't get the whole earth - the most you can get is the >> cube that fits within it. I can look into adding that functionality for >> the aeqd projection if there's a real use case. Note that there are >> other whole-earth projections available (mollweide, vandergrinten, >> robinson, sinuisoidal etc). These projections have much less distortion >> far away from the center of the map than the azimuthal equidistant >> does. Why do you want to use aeqd to plot the whole globe? >> >> -Jeff >> >>> Thanks, >>> >>> Rob >>> >>> >> >>> John [H2O] wrote: >>> >>> >>>> Hello, >>>> >>>> I'm creating a web application that will take user input from a >>>> javascript >>>> map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, >>>> llcrnrlat, >>>> llcrnrlon) and possibly a switch for polar projection. Other than that I >>>> have no further information. Which projection is the most suitable to >>>> handle anything from a 'global' plot to a zoom say over a state? I don't >>>> see the zoom being too tight, but global projections are likely. I >>>> personally prefer Equal Area, hence right now I'm working with 'aeqd', >>>> but >>>> I seem to have problems if the plot is global with that projection. >>>> >>>> Just looking for advice, opinions, and ideally examples if anyone has >>>> created a similar function / module to use in a web environment. >>>> >>>> Thanks! >>>> -john >>>> >>>> >>>> >>> >>> >> -- >> 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 >> >> >> ------------------------------------------------------------------------------ >> _______________________________________________ >> Matplotlib-users mailing list >> Mat...@li... >> https://lists.sourceforge.net/lists/listinfo/matplotlib-users >> >> >> > >
Thanks Jeff! That is just wonderful! No need for a non-spherical earth model for me. Again, thanks! Rob Jeff Whitaker wrote: > > Rob Frohne wrote: >> Hi Jeff, >> >> I am an amateur radio operator, and I am writing a little application to >> display where the major lobe of my antenna is pointing. I can control >> the >> direction of my antenna with the computer, and it would be nice to have a >> display of the whole world, as well as circles representing how far the >> station I am talking to is, and radial lines showing the bearings. I'd >> like >> to show the bearings along the edge of the map. For this type of map, a >> circle is a much better boundary than a square, but if it has to be a >> square, we should be able to make it a square bounding the circle, not >> the >> other way around. I think I can even plot the station's location given >> data >> I get from the Internet using this software. I am just learning Python, >> but >> it appears to be ideal for what I'm doing. >> >> Right now I'm trying to figure out how to get the Eclipse IDE I am trying >> out to show me the source code for Basemap. :-) >> >> Thanks for the expert help! >> >> Rob >> > > Rob: I've updated basemap in SVN so that if neither a width/height or > corner lat/lons are provided, the whole world is plotted in a circle > with projection='aeqd'. If you can access SVN please try it out and let > me know how it works for you. If not, I can provide you with a tarball. > > The full-disk aeqd will not work right now with ellipsoids, only for > perfect spheres. Is that a problem for you? > > -Jeff >> Jeff Whitaker wrote: >> >>> Rob Frohne wrote: >>> >>>> Hi, >>>> >>>> I think I am running into the same thing John is here. When you want >>>> to >>>> display the whole earth in 'aeqd' mode, the projection needs to be onto >>>> a >>>> circle. As it is, what is plotted is a square that just fits inside >>>> the >>>> circle I want. Here is a link to a photo of the kind of projection I >>>> want. >>>> >>>> http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif >>>> >>>> Is there a way to get the whole earth plotted with 'aeqd'? >>>> >>>> >>> Rob: No, you can't get the whole earth - the most you can get is the >>> cube that fits within it. I can look into adding that functionality for >>> the aeqd projection if there's a real use case. Note that there are >>> other whole-earth projections available (mollweide, vandergrinten, >>> robinson, sinuisoidal etc). These projections have much less distortion >>> far away from the center of the map than the azimuthal equidistant >>> does. Why do you want to use aeqd to plot the whole globe? >>> >>> -Jeff >>> >>>> Thanks, >>>> >>>> Rob >>>> >>>> >>> >>>> John [H2O] wrote: >>>> >>>> >>>>> Hello, >>>>> >>>>> I'm creating a web application that will take user input from a >>>>> javascript >>>>> map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, >>>>> llcrnrlat, >>>>> llcrnrlon) and possibly a switch for polar projection. Other than that >>>>> I >>>>> have no further information. Which projection is the most suitable to >>>>> handle anything from a 'global' plot to a zoom say over a state? I >>>>> don't >>>>> see the zoom being too tight, but global projections are likely. I >>>>> personally prefer Equal Area, hence right now I'm working with 'aeqd', >>>>> but >>>>> I seem to have problems if the plot is global with that projection. >>>>> >>>>> Just looking for advice, opinions, and ideally examples if anyone has >>>>> created a similar function / module to use in a web environment. >>>>> >>>>> Thanks! >>>>> -john >>>>> >>>>> >>>>> >>>> >>>> >>> -- >>> 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 >>> >>> >>> ------------------------------------------------------------------------------ >>> _______________________________________________ >>> Matplotlib-users mailing list >>> Mat...@li... >>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users >>> >>> >>> >> >> > > > ------------------------------------------------------------------------------ > _______________________________________________ > Matplotlib-users mailing list > Mat...@li... > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > -- View this message in context: http://www.nabble.com/dynamic-basemap-tp20121594p21234584.html Sent from the matplotlib - users mailing list archive at Nabble.com.
Hi Jeff, I am an amateur radio operator, and I am writing a little application to display where the major lobe of my antenna is pointing. I can control the direction of my antenna with the computer, and it would be nice to have a display of the whole world, as well as circles representing how far the station I am talking to is, and radial lines showing the bearings. I'd like to show the bearings along the edge of the map. For this type of map, a circle is a much better boundary than a square, but if it has to be a square, we should be able to make it a square bounding the circle, not the other way around. I think I can even plot the station's location given data I get from the Internet using this software. I am just learning Python, but it appears to be ideal for what I'm doing. Right now I'm trying to figure out how to get the Eclipse IDE I am trying out to show me the source code for Basemap. :-) Thanks for the expert help! Rob Jeff Whitaker wrote: > > Rob Frohne wrote: >> Hi, >> >> I think I am running into the same thing John is here. When you want to >> display the whole earth in 'aeqd' mode, the projection needs to be onto a >> circle. As it is, what is plotted is a square that just fits inside the >> circle I want. Here is a link to a photo of the kind of projection I >> want. >> >> http://www.wm7d.net/az_proj/images/lon_anim_shaded.gif >> >> Is there a way to get the whole earth plotted with 'aeqd'? >> > > Rob: No, you can't get the whole earth - the most you can get is the > cube that fits within it. I can look into adding that functionality for > the aeqd projection if there's a real use case. Note that there are > other whole-earth projections available (mollweide, vandergrinten, > robinson, sinuisoidal etc). These projections have much less distortion > far away from the center of the map than the azimuthal equidistant > does. Why do you want to use aeqd to plot the whole globe? > > -Jeff >> Thanks, >> >> Rob >> > > >> >> John [H2O] wrote: >> >>> Hello, >>> >>> I'm creating a web application that will take user input from a >>> javascript >>> map to give me bounding coordinates (i.e. urcrnrlat, urcrnrlon, >>> llcrnrlat, >>> llcrnrlon) and possibly a switch for polar projection. Other than that I >>> have no further information. Which projection is the most suitable to >>> handle anything from a 'global' plot to a zoom say over a state? I don't >>> see the zoom being too tight, but global projections are likely. I >>> personally prefer Equal Area, hence right now I'm working with 'aeqd', >>> but >>> I seem to have problems if the plot is global with that projection. >>> >>> Just looking for advice, opinions, and ideally examples if anyone has >>> created a similar function / module to use in a web environment. >>> >>> Thanks! >>> -john >>> >>> >> >> > > > -- > 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 > > > ------------------------------------------------------------------------------ > _______________________________________________ > Matplotlib-users mailing list > Mat...@li... > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > -- View this message in context: http://www.nabble.com/dynamic-basemap-tp20121594p21225725.html Sent from the matplotlib - users mailing list archive at Nabble.com.
