baselayers incorrect for some 'sper' projections.
Nobody has claimed this yet.
Assessment
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Newbie friendliness
- 35/100
- Issue type
- Bug
- Clarity
- Mostly clear
- Activity status
- Stale
- Tech stack
- python
- Domain
- data-visualization
Research direction
Reproduce the issue with the two Basemap examples, comparing shadedrelief, bluemarble, and etopo when nsper uses explicit llcrnrx, llcrnry, urcrnrx, and urcrnry values. Start from the Basemap projection and shadedrelief entry points, using the linked gist and screenshot as references. Done means the base layers display correctly with the explicit corner coordinates.
Written by the indexing model from the issue text.
Description
This may be related to #168, but might not.
If your 'sper' basemap is set up to choose corners using xy values, then the baselayers
are not displayed properly. These all fail: bluemarble, shadedrelief, and etopo.
Any help would be great.
Thanks
Does what I expect:
h = 15000.; lon_0 = -115; lat_0 = 55
m = Basemap(projection='nsper',satellite_height=h*1000.,\
lon_0=lon_0,lat_0=lat_0,resolution='l')
m.drawparallels(np.arange(-90.,120.,30.))
m.drawcoastlines()
m.shadedrelief(scale=.2)
Fails to correctly display the base layer.
m = Basemap(projection='nsper',satellite_height=h*1000.,\
lon_0=lon_0,lat_0=lat_0,resolution='l',\
llcrnrx=-4000000,llcrnry=0,urcrnrx=4000000,urcrnry=5000000)
m.drawparallels(np.arange(-90.,120.,30.))
m.drawcoastlines()
m.shadedrelief(scale=.2)
Here's a gist with what I'm seeing
https://gist.github.com/flamingbear/76eeb588c006965361c6
and a screenshot.

- Dominant language
- Python
- Stars
- 817
- Forks
- 395
- PR merge metrics
- No merged PRs in 30d
Contributor guide
No contributing guide indexed for this repository
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
More from matplotlib/basemap
-
Difficulty 2/5 1-3 hours Newbie friendliness 68/100
matplotlib/basemap#368 ·
-
Python 3.14 wheels Open
Difficulty 4/5 3-5 days Newbie friendliness 48/100
matplotlib/basemap#652 · 2 comments · 5 reactions ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 45/100
matplotlib/basemap#649 · 2 reactions ·
-
Difficulty 5/5 Over a week Newbie friendliness 35/100
matplotlib/basemap#646 ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 48/100
matplotlib/basemap#645 · 2 comments ·
All issues in matplotlib/basemap
Similar issues
-
essnmx good first issue
Difficulty 1/5 Under an hour Newbie friendliness 95/100
-
[Feature] 奇物选择添加优先级 Open
Difficulty 2/5 1-3 hours Newbie friendliness 65/100
syfoud/Simulated_Scepter#174 ·
-
Difficulty 2/5 1-3 hours Newbie friendliness 75/100
Giskard-AI/giskard-oss#2840 · 1 comment ·
-
A claim comment carrying the issue number is silently declined while the workflow reports success Openarea: repo bug perceived difficulty: 2
Difficulty 2/5 1-3 hours Newbie friendliness 70/100
-
Difficulty 2/5 1-3 hours Newbie friendliness 75/100
yeti-platform/yeti#1380 ·