Mathew Yeates wrote: > lets say I want to shade the area with lat/lon corners 34.-117 and > 35,-116 > > but my map was created with projection='aeqd' > > The shade area will not be a rectangle. In fact the edges will be > curved. See the basemap code for "tissot". I think every point on the > boundary of the lat/lon box has to projected to a line segment. The > collection of resulting segments forms an irregular polygon. > > Mathew
Mathew: Right - it will only be a rectangle in a cylindrical projection. The question remains - what do you want? If you want a rectangle in map projection coordinates, just specify the vertices of a rectangle in map projection coordinates. If you really want a polygon with vertices corresponding to those lat/on values, a polygon with curved sides is the right answer for that map projection. -Jeff > > > > > On Wed, Apr 7, 2010 at 6:24 PM, Jeff Whitaker <jsw...@fastmail.fm > <mailto:jsw...@fastmail.fm>> wrote: > > Mathew Yeates wrote: > > I think this will only work with some projections but not all. > I looked at the code for tissot. It's pretty hairy but it > almost does what I want. (It draws projected circles > instead of projected rectangles. > > Mathew: > > You said you wanted a NxN degree polygon - that's what I gave you. > What exactly do you want? A rectangle in map projection > coordinates? A rectangle in lat/lon coordinates? A circle? > > -Jeff > > > > On Wed, Apr 7, 2010 at 1:54 PM, Jeff Whitaker > <jsw...@fastmail.fm <mailto:jsw...@fastmail.fm> > <mailto:jsw...@fastmail.fm <mailto:jsw...@fastmail.fm>>> wrote: > > Yeates, Mathew C (388D) wrote: > > > > > > > > Hi > > > > What is the simplest way to fill in a 1 degree by 1 degree > rectangle > > on a basemap projection? > > > > > > > > Mathew > > > > Mathew: Try this (for a 10x10 rectangle, but you get the idea) > > from matplotlib.patches import Polygon > import matplotlib.pyplot as plt > from mpl_toolkits.basemap import Basemap > map = Basemap(projection='moll',lon_0=0) > x1,y1 = map(-10,-10) > x2,y2 = map(-10,10) > x3,y3 = map(10,10) > x4,y4 = map(10,-10) > p = Polygon([(x1,y1),(x2,y2),(x3,y3),(x4,y4)],\ > facecolor='red',edgecolor='blue',linewidth=2) > plt.gca().add_patch(p) > map.drawcoastlines() > map.drawmapboundary() > plt.show() > > -Jeff > > > > > > > ------------------------------------------------------------------------------ > Download Intel® Parallel Studio Eval > Try the new software tools for yourself. Speed compiling, > find bugs > proactively, and fine-tune applications for parallel > performance. > See why Intel Parallel Studio got high marks during beta. > http://p.sf.net/sfu/intel-sw-dev > _______________________________________________ > Matplotlib-users mailing list > Matplotlib-users@lists.sourceforge.net > <mailto:Matplotlib-users@lists.sourceforge.net> > <mailto:Matplotlib-users@lists.sourceforge.net > <mailto:Matplotlib-users@lists.sourceforge.net>> > > https://lists.sourceforge.net/lists/listinfo/matplotlib-users > > > > ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
