Re: [Matplotlib-users] Basemap: Coastlines intersecting with map boundary
Jeff, thanks for your feedback! Jeff Whitaker [15.09.2012 17:25]: On 9/15/12 8:05 AM, Joachim Saul wrote: Hi there, in basemap coastlines are apparently (always?) drawn as closed polygons not exceeding the map boundary, i.e. when the coastline intersects with the map boundary the polygon is continued along the map boundary until the next intersection point. The somewhat annoying side effect of this is a map boundary that appears thicker where it crosses landmasses. See for instance on http://matplotlib.org/basemap/users/examples the example Plot hurricane tracks from a shapefile where clearly the upper and left map boundaries are thicker where they cross the western U.S. or northern Canada. Another example where this effect is particularly pronounced is the example Draw great circle between NY and London on the same page. The effect gets worse if running these examples without antialiasing. Apparently only the upper and left boundaries are affected, whereas the lower and right boundaries are plotted properly. It looks to me as if this might simply be a bug due to the coastline not aligning perfectly with the map boundary, perhaps because of some roundoff error. Is there a way to avoid this? Wouldn't it be better to draw the coastlines not as closed polygons but as collections of line segments? Cheers, Joachim Joachim: I've noticed this myself, but have not found any solution. I suppose I could add an option to treat coastlines as line segments, but then you would not be able to use the fillcontinents method. On the other hand, computing the coastlines /either/ as segments /or/ closed polygons might be inexpensive enough to be done on the fly - i.e. segments in drawcoastlines() but closed polygons in fillcontinents(). A computational penalty comes into play only where both are called. But I think this would be acceptable. Here's what happens now when a Basemap instance is created: 1) the intersection between the coastline polygons and the map boundary is computed using the geos C library. 2) the coastline polygons are clipped at the map boundary 3) the coordinates of the coastline polygons are transformed to map projection coordinates Then, when the drawcoastlines or fillcontinents methods are called only the polygons inside the map projection region are drawn. This saves *a lot* of time when you're using high-resolution coastlines in a small map region. There is a similar process for political boundaries, but since they are line segments you don't see the thickening around the map edges. Generally speaking this optimization stragegy is absolutely fine and works well - except for this nasty little line width artefact. ;) Maybe one solution would be to clip the polygons to a region slightly larger than the actual map projection region. That should work but on the other hand it seems a little hackish and the resulting code could be harder to understand. Besides the suggestion given above I still have the feeling that part of the problem might be related to some roundoff issue - how else could the presence of thickened lines be (apparently) confined to only the upper and left border? Cheers, Joachim -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Problem with axvline in gridspec with log Y axis
Sometimes, having a point of reference really helps in tracking the issue down, particularly when complimented with the very cool bisect tool that comes with git. In this case though, I knew where the problem came in because I have been working closely in this area recently (and it's my change which has exposed the problem). I have fixed this in the pull request, and fully expect the fix to be in the next 1.2.x release candidate. If your willing and able, you could get hold of my branch until it is merged to carry on testing the release candidate. Hope that helps, All the best, Phil On 14 September 2012 17:53, Scott Lasley slas...@space.umd.edu wrote: On Sep 14, 2012, at 5:02 AM, Phil Elson pelson@gmail.com wrote: Thanks for raising this. I have simplified and opened an issue for the bug (https://github.com/matplotlib/matplotlib/issues/1246) and will be looking at this asap. All the best, Phil I don't know if this helps, but my scripts and the code snippet in my email message work without crashing using matplotlib 1.2.x compiled from github on July 23, 2012 and numpy-1.8.0.dev_63cd8f3-py2.7-macosx-10.6-intel.egg on another mac running OS X 10.8.1. Thank you for looking into this, Scott -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] sharex with different tick labels
From: Daniel Welling [mailto:dantwell...@gmail.com] Sent: Thursday, September 13, 2012 16:23 Greetings, all. I have an issue: I have several axes stacked in a column with a common time vector on each x-axis. Each plot is a contour, so overplotting is not an option. In a perfect world, I want the following: 1) The subplots are tightly spaced such that with ax.grid() activated, the grid lines appear continuous. This makes comparing simultaneous characteristics between subplots very easy. 2) The subplots are linked via the sharex keyword so I can move them all in unison. 3) Only the bottommost subplot has x tick labels; on other plots, the long time-formatted labels stick out of the left and right of the plots. [...] For #3, there is a convenience method of subplots, label_outer [1], that sets the visibility of the tick labels (as Francesco described), making them visible in the bottom row and invisible elsewhere (as in Sterling's code). Just iterate over all of your subplots and call the label_outer method on each one. [1] http://matplotlib.org/api/axes_api.html#matplotlib.axes.SubplotBase.label_oute r -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Basemap: Coastlines intersecting with map boundary
On 9/17/12 5:09 AM, Joachim Saul wrote: Jeff, thanks for your feedback! A workaround for this (having drawcoastlines use line segments instead of polygons) is now part of this pull request: https://github.com/matplotlib/basemap/pull/78 Let's move discussion there.. -Jeff Jeff Whitaker [15.09.2012 17:25]: On 9/15/12 8:05 AM, Joachim Saul wrote: Hi there, in basemap coastlines are apparently (always?) drawn as closed polygons not exceeding the map boundary, i.e. when the coastline intersects with the map boundary the polygon is continued along the map boundary until the next intersection point. The somewhat annoying side effect of this is a map boundary that appears thicker where it crosses landmasses. See for instance on http://matplotlib.org/basemap/users/examples the example Plot hurricane tracks from a shapefile where clearly the upper and left map boundaries are thicker where they cross the western U.S. or northern Canada. Another example where this effect is particularly pronounced is the example Draw great circle between NY and London on the same page. The effect gets worse if running these examples without antialiasing. Apparently only the upper and left boundaries are affected, whereas the lower and right boundaries are plotted properly. It looks to me as if this might simply be a bug due to the coastline not aligning perfectly with the map boundary, perhaps because of some roundoff error. Is there a way to avoid this? Wouldn't it be better to draw the coastlines not as closed polygons but as collections of line segments? Cheers, Joachim Joachim: I've noticed this myself, but have not found any solution. I suppose I could add an option to treat coastlines as line segments, but then you would not be able to use the fillcontinents method. On the other hand, computing the coastlines /either/ as segments /or/ closed polygons might be inexpensive enough to be done on the fly - i.e. segments in drawcoastlines() but closed polygons in fillcontinents(). A computational penalty comes into play only where both are called. But I think this would be acceptable. Here's what happens now when a Basemap instance is created: 1) the intersection between the coastline polygons and the map boundary is computed using the geos C library. 2) the coastline polygons are clipped at the map boundary 3) the coordinates of the coastline polygons are transformed to map projection coordinates Then, when the drawcoastlines or fillcontinents methods are called only the polygons inside the map projection region are drawn. This saves *a lot* of time when you're using high-resolution coastlines in a small map region. There is a similar process for political boundaries, but since they are line segments you don't see the thickening around the map edges. Generally speaking this optimization stragegy is absolutely fine and works well - except for this nasty little line width artefact. ;) Maybe one solution would be to clip the polygons to a region slightly larger than the actual map projection region. That should work but on the other hand it seems a little hackish and the resulting code could be harder to understand. Besides the suggestion given above I still have the feeling that part of the problem might be related to some roundoff issue - how else could the presence of thickened lines be (apparently) confined to only the upper and left border? Cheers, Joachim -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Jeffrey S. Whitaker Phone : (303)497-6313 Meteorologist FAX: (303)497-6449 NOAA/OAR/PSD R/PSD1Email : jeffrey.s.whita...@noaa.gov 325 BroadwayOffice : Skaggs Research Cntr 1D-113 Boulder, CO, USA 80303-3328 Web: http://tinyurl.com/5telg -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] broken links at github
hi all, a lot of links at the github repository are broken. for example all the links to png, source code, ... of the image tutorial (http://matplotlib.org/users/image_tutorial.html). but also links of other pages are broken (e.g. http://matplotlib.org/users/plotting/examples/demo_gridspec01.png or http://matplotlib.org/users/tight_layout_guide.html or ) and a lot of google search results. best regards christian -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] broken links at github
Thanks for pointing this out. I'll get to the bottom of it. Mike On 09/17/2012 05:16 PM, christian.str...@dlr.de wrote: hi all, a lot of links at the github repository are broken. for example all the links to png, source code, ... of the image tutorial (http://matplotlib.org/users/image_tutorial.html). but also links of other pages are broken (e.g. http://matplotlib.org/users/plotting/examples/demo_gridspec01.png or http://matplotlib.org/users/tight_layout_guide.html or ) and a lot of google search results. best regards christian -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] broken links at github
thanks for your fast help. the links for the image tutorial are working already again. On Sep 17, 2012, at 11:53 PM, Michael Droettboom wrote: Thanks for pointing this out. I'll get to the bottom of it. Mike On 09/17/2012 05:16 PM, christian.str...@dlr.de wrote: hi all, a lot of links at the github repository are broken. for example all the links to png, source code, ... of the image tutorial (http://matplotlib.org/users/image_tutorial.html). but also links of other pages are broken (e.g. http://matplotlib.org/users/plotting/examples/demo_gridspec01.png or http://matplotlib.org/users/tight_layout_guide.html or ) and a lot of google search results. best regards christian -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] broken links at github
Thanks. I believe it should all be fixed now. On 09/17/2012 06:33 PM, christian.str...@dlr.de wrote: thanks for your fast help. the links for the image tutorial are working already again. On Sep 17, 2012, at 11:53 PM, Michael Droettboom wrote: Thanks for pointing this out. I'll get to the bottom of it. Mike On 09/17/2012 05:16 PM, christian.str...@dlr.de wrote: hi all, a lot of links at the github repository are broken. for example all the links to png, source code, ... of the image tutorial (http://matplotlib.org/users/image_tutorial.html). but also links of other pages are broken (e.g. http://matplotlib.org/users/plotting/examples/demo_gridspec01.png or http://matplotlib.org/users/tight_layout_guide.html or ) and a lot of google search results. best regards christian -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
