[Matplotlib-users] matplotlib/basemap plot geo data on background map
Hi, I'm new to matplotlib and I'm looking for an easy way to plot geographical data on a background map: bkgmap.png http://old.nabble.com/file/p29679002/bkgmap.png So far I only found out about warpimage() to do this but only part of bkgmap.png comes up in the output image. I think this is because this image has no pixels covering all the world. http://old.nabble.com/file/p29679002/partialbkg_polygon.png Any idea on how to insert this image as background? THANKS Code: the polygon displays in right position even though background doesn't show OK (tested with map,lat/lon lines drawn too) import sys import Image, ImageDraw # PIL from matplotlib.patches import Polygon from mpl_toolkits.basemap import Basemap import matplotlib.image as mpimg import matplotlib.pyplot as plt import numpy as np lat0=48 lon0=13 lllon=-15 lllat=20 urlon=73 urlat=57 map = Basemap(projection='stere',lat_0=lat0,lon_0=lon0,llcrnrlon=lllon,llcrnrlat=lllat,urcrnrlon=urlon,urcrnrlat=urlat, resolution='c',area_thresh=1000.) map.warpimage(image='bkgmap.png',scale=None,ax=plt.gca()) # points lat = [50.,55.,45.,40.,50.] lon = [-20.,-10.,10.,-10.,-20.] x0,y0 = map(lon[0],lat[0]) x1,y1 = map(lon[1],lat[1]) x2,y2 = map(lon[2],lat[2]) x3,y3 = map(lon[3],lat[3]) x4,y4 = map(lon[4],lat[4]) plt.gca().add_patch(Polygon([(x0,y0),(x1,y1),(x2,y2),(x3,y3),(x4,y4)],fill=1,facecolor='red',edgecolor='black')) plt.show() -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679002.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] matplotlib/basemap plot geo data on background map
If you're just looking for points, you can use ax.scatter(). It will plot the points. Also, make sure you set the zorder keyword argument in the scatter. Example: x=range(10) y=range(10) z=range(10,20) ax.scatter(x,y,c=z,zorder=10) Hope this helps, Aman On Fri, Sep 10, 2010 at 1:06 PM, izzybitsie isid...@juno.com wrote: Hi, I'm new to matplotlib and I'm looking for an easy way to plot geographical data on a background map: bkgmap.png http://old.nabble.com/file/p29679002/bkgmap.png So far I only found out about warpimage() to do this but only part of bkgmap.png comes up in the output image. I think this is because this image has no pixels covering all the world. http://old.nabble.com/file/p29679002/partialbkg_polygon.png Any idea on how to insert this image as background? THANKS Code: the polygon displays in right position even though background doesn't show OK (tested with map,lat/lon lines drawn too) import sys import Image, ImageDraw # PIL from matplotlib.patches import Polygon from mpl_toolkits.basemap import Basemap import matplotlib.image as mpimg import matplotlib.pyplot as plt import numpy as np lat0=48 lon0=13 lllon=-15 lllat=20 urlon=73 urlat=57 map = Basemap(projection='stere',lat_0=lat0,lon_0=lon0,llcrnrlon=lllon,llcrnrlat=lllat,urcrnrlon=urlon,urcrnrlat=urlat, resolution='c',area_thresh=1000.) map.warpimage(image='bkgmap.png',scale=None,ax=plt.gca()) # points lat = [50.,55.,45.,40.,50.] lon = [-20.,-10.,10.,-10.,-20.] x0,y0 = map(lon[0],lat[0]) x1,y1 = map(lon[1],lat[1]) x2,y2 = map(lon[2],lat[2]) x3,y3 = map(lon[3],lat[3]) x4,y4 = map(lon[4],lat[4]) plt.gca().add_patch(Polygon([(x0,y0),(x1,y1),(x2,y2),(x3,y3),(x4,y4)],fill=1,facecolor='red',edgecolor='black')) plt.show() -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679002.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Aman Thakral B.Eng Biosci, M.Eng Design -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] matplotlib/basemap plot geo data on background map
Hi, documentation of mpl_toolkits.basemap.warpimage (http://matplotlib.sourceforge.net/basemap/doc/html/api/basemap_api.html#mpl_toolkits.basemap.Basemap.warpimage) states that it could only be used with a very specific set of images: Specified image must have pixels covering the whole globe in a regular lat/lon grid, starting and -180W and the South Pole., so your image won't work - it is curved, there is no obvious (linear) transformation from (x,y) to (lat, long). Examples of good images are given here: http://earthobservatory.nasa.gov/Features/BlueMarble/BlueMarble_monthlies.php There are easy ways to mimic your picture with native Basemap tools, like in this examples: http://matplotlib.sourceforge.net/basemap/doc/html/users/geography.html But if you would specifically use your own image, the only way I see is to come up with a transformation function transforming lat and long coordinates to x,y coordinates of your specific picture. If you would write such a function yourself than you could easily use ax.plot, ax.scatter or any other plotting routine to place stuff in correct place in respect to your picture. Giving (lat, long) of stuff you would like to draw, than transforming to (x,y) with the function, and than using those with plotting routines at the same axis you have place your picture, with for example imshow routine with proper zorder. Hope this clears a problem a little bit, JS On Fri, Sep 10, 2010 at 13:06, izzybitsie isid...@juno.com wrote: Hi, I'm new to matplotlib and I'm looking for an easy way to plot geographical data on a background map: bkgmap.png http://old.nabble.com/file/p29679002/bkgmap.png So far I only found out about warpimage() to do this but only part of bkgmap.png comes up in the output image. I think this is because this image has no pixels covering all the world. http://old.nabble.com/file/p29679002/partialbkg_polygon.png Any idea on how to insert this image as background? THANKS Code: the polygon displays in right position even though background doesn't show OK (tested with map,lat/lon lines drawn too) import sys import Image, ImageDraw # PIL from matplotlib.patches import Polygon from mpl_toolkits.basemap import Basemap import matplotlib.image as mpimg import matplotlib.pyplot as plt import numpy as np lat0=48 lon0=13 lllon=-15 lllat=20 urlon=73 urlat=57 map = Basemap(projection='stere',lat_0=lat0,lon_0=lon0,llcrnrlon=lllon,llcrnrlat=lllat,urcrnrlon=urlon,urcrnrlat=urlat, resolution='c',area_thresh=1000.) map.warpimage(image='bkgmap.png',scale=None,ax=plt.gca()) # points lat = [50.,55.,45.,40.,50.] lon = [-20.,-10.,10.,-10.,-20.] x0,y0 = map(lon[0],lat[0]) x1,y1 = map(lon[1],lat[1]) x2,y2 = map(lon[2],lat[2]) x3,y3 = map(lon[3],lat[3]) x4,y4 = map(lon[4],lat[4]) plt.gca().add_patch(Polygon([(x0,y0),(x1,y1),(x2,y2),(x3,y3),(x4,y4)],fill=1,facecolor='red',edgecolor='black')) plt.show() -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679002.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] matplotlib/basemap plot geo data on background map
Thanks for your answer. I'm actually looking to plot filled curves whose points are lat/lon points on top of a given background map. The problem experienced is misrepresentation of background map when I insert it using warpimage(), the only function to do this I found so far. Aman Thakral wrote: If you're just looking for points, you can use ax.scatter(). It will plot the points. Also, make sure you set the zorder keyword argument in the scatter. Example: x=range(10) y=range(10) z=range(10,20) ax.scatter(x,y,c=z,zorder=10) Hope this helps, Aman On Fri, Sep 10, 2010 at 1:06 PM, izzybitsie isid...@juno.com wrote: Hi, I'm new to matplotlib and I'm looking for an easy way to plot geographical data on a background map: bkgmap.png http://old.nabble.com/file/p29679002/bkgmap.png So far I only found out about warpimage() to do this but only part of bkgmap.png comes up in the output image. I think this is because this image has no pixels covering all the world. http://old.nabble.com/file/p29679002/partialbkg_polygon.png Any idea on how to insert this image as background? THANKS Code: the polygon displays in right position even though background doesn't show OK (tested with map,lat/lon lines drawn too) import sys import Image, ImageDraw # PIL from matplotlib.patches import Polygon from mpl_toolkits.basemap import Basemap import matplotlib.image as mpimg import matplotlib.pyplot as plt import numpy as np lat0=48 lon0=13 lllon=-15 lllat=20 urlon=73 urlat=57 map = Basemap(projection='stere',lat_0=lat0,lon_0=lon0,llcrnrlon=lllon,llcrnrlat=lllat,urcrnrlon=urlon,urcrnrlat=urlat, resolution='c',area_thresh=1000.) map.warpimage(image='bkgmap.png',scale=None,ax=plt.gca()) # points lat = [50.,55.,45.,40.,50.] lon = [-20.,-10.,10.,-10.,-20.] x0,y0 = map(lon[0],lat[0]) x1,y1 = map(lon[1],lat[1]) x2,y2 = map(lon[2],lat[2]) x3,y3 = map(lon[3],lat[3]) x4,y4 = map(lon[4],lat[4]) plt.gca().add_patch(Polygon([(x0,y0),(x1,y1),(x2,y2),(x3,y3),(x4,y4)],fill=1,facecolor='red',edgecolor='black')) plt.show() -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679002.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Aman Thakral B.Eng Biosci, M.Eng Design -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679748.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] matplotlib/basemap plot geo data on background map
I tested the same plot with a background image in Mercator with same results and I also tested with Mercator covering almost the entire world with the same results. Only a little portion of the background image shows as background although the polygon looks OK in all cases (with maps drawn and with either background image). Unfortunately, I must use the provided background images for my project. I may need to look for some other tool to accomplish drawing curves on a provided background image instead of relying on matplotlib. I did not understand the need for me to write my own transformation functions. I only used lat/lon-x/y for the points in the curve and the polygon shows up OK. What should I write my own transformations for? THANKS izzybitsie wrote: Thanks for your answer. I'm actually looking to plot filled curves whose points are lat/lon points on top of a given background map. The problem experienced is misrepresentation of background map when I insert it using warpimage(), the only function to do this I found so far. Aman Thakral wrote: If you're just looking for points, you can use ax.scatter(). It will plot the points. Also, make sure you set the zorder keyword argument in the scatter. Example: x=range(10) y=range(10) z=range(10,20) ax.scatter(x,y,c=z,zorder=10) Hope this helps, Aman On Fri, Sep 10, 2010 at 1:06 PM, izzybitsie isid...@juno.com wrote: Hi, I'm new to matplotlib and I'm looking for an easy way to plot geographical data on a background map: bkgmap.png http://old.nabble.com/file/p29679002/bkgmap.png So far I only found out about warpimage() to do this but only part of bkgmap.png comes up in the output image. I think this is because this image has no pixels covering all the world. http://old.nabble.com/file/p29679002/partialbkg_polygon.png Any idea on how to insert this image as background? THANKS Code: the polygon displays in right position even though background doesn't show OK (tested with map,lat/lon lines drawn too) import sys import Image, ImageDraw # PIL from matplotlib.patches import Polygon from mpl_toolkits.basemap import Basemap import matplotlib.image as mpimg import matplotlib.pyplot as plt import numpy as np lat0=48 lon0=13 lllon=-15 lllat=20 urlon=73 urlat=57 map = Basemap(projection='stere',lat_0=lat0,lon_0=lon0,llcrnrlon=lllon,llcrnrlat=lllat,urcrnrlon=urlon,urcrnrlat=urlat, resolution='c',area_thresh=1000.) map.warpimage(image='bkgmap.png',scale=None,ax=plt.gca()) # points lat = [50.,55.,45.,40.,50.] lon = [-20.,-10.,10.,-10.,-20.] x0,y0 = map(lon[0],lat[0]) x1,y1 = map(lon[1],lat[1]) x2,y2 = map(lon[2],lat[2]) x3,y3 = map(lon[3],lat[3]) x4,y4 = map(lon[4],lat[4]) plt.gca().add_patch(Polygon([(x0,y0),(x1,y1),(x2,y2),(x3,y3),(x4,y4)],fill=1,facecolor='red',edgecolor='black')) plt.show() -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679002.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Aman Thakral B.Eng Biosci, M.Eng Design -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- View this message in context: http://old.nabble.com/matplotlib-basemap-plot-geo-data-on-background-map-tp29679002p29679934.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] matplotlib/basemap plot geo data on background map
On Fri, Sep 10, 2010 at 14:46, izzybitsie isid...@juno.com wrote: I did not understand the need for me to write my own transformation functions. I only used lat/lon-x/y for the points in the curve and the polygon shows up OK. What should I write my own transformations for? Because matplotlib (and possibly any other tool out there) have absolutely no idea what transformation have you used to generate your background picture in the first place. If you want to match grid of coordinates of you picture with the grid of coordinates of what you are trying to plot on top of it, you have to input this information somehow. And one possible way of doing this is taking a transformation function which will be exactly the same as one used to generate your background. I do not think there is some other, magical way of doing this. This is not a matplotlib specific problem, it is a general problem. But maybe someone else will correct me if I am wrong. JS -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing http://p.sf.net/sfu/novell-sfdev2dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
