readshapefile fails on certain filenames

[matplotlib]

readshapefile fails on certain filenames

[guziy]

Hmm:

I look at the code and do not understand how it worked for you .... What
happens if you don't specify the .shp extension?

Thanks

2014-04-28 18:10 GMT-04:00 Andy Aschwanden [email protected]:

Hi,

(Tested with basemap 1.0.6)

This works:

m.readshapefile('foo.shp', 'my_shape')

while this fails:

m.readshapefile('bar_0.1.shp', 'my_shape')

raise IOError('error reading shapefile %s.shp' % shapefile)
fields = shf.fields
coords = []; attributes = []

IOError: error reading shapefile bar_0.1.shp

Note that foo.shp and bar_0.1.shp are exactly the same file except for the
filename. So it seems that the additional . causes the problem. Minimal
example to reproduce behavior:

Rename huralll020.{shp,dfb,shx} to huralll020_0.1.{shp,dbf,shx} and
change filename in examples/hurrtracks.py accordingly. Run hurrtracks.py.

Of course the obvious workaround is not to use . in filenames. But this
is somewhat impracticable as I have a large number or files and would like
keeping the filenames consistent accross filetypes (netCDF, shapfiles,
pngs, etc).

Is there an easy fix?

Thanks very much,

Andy

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/151
.

Sasha

[aaschwanden]

Sorry, I was not clear enough, the above code was a snippet from my scripts. I don't specify the the .shp extension, so the above should read:

This works:

m.readshapefile('foo, 'my_shape')

while this fails:

m.readshapefile('bar_0.1', 'my_shape')

Andy

[guziy]

I think you are not passing the extension to readshapefile, it is just a
typo in your example, right?

If this is so then the culprit is this line:

https://github.com/matplotlib/basemap/blob/master/lib/mpl_toolkits/basemap/shapefile.py#L249

It is not to hard to fix, so If you want the glory, go ahead) If Jeff won't
mind.

Cheers

2014-04-28 18:31 GMT-04:00 Oleksandr Huziy [email protected]:

Hmm:

I look at the code and do not understand how it worked for you .... What
happens if you don't specify the .shp extension?

Thanks

2014-04-28 18:10 GMT-04:00 Andy Aschwanden [email protected]:

Hi,

(Tested with basemap 1.0.6)

This works:

m.readshapefile('foo.shp', 'my_shape')

while this fails:

m.readshapefile('bar_0.1.shp', 'my_shape')

raise IOError('error reading shapefile %s.shp' % shapefile)
fields = shf.fields
coords = []; attributes = []

IOError: error reading shapefile bar_0.1.shp

Note that foo.shp and bar_0.1.shp are exactly the same file except for
the filename. So it seems that the additional . causes the problem.
Minimal example to reproduce behavior:

Rename huralll020.{shp,dfb,shx} to huralll020_0.1.{shp,dbf,shx} and
change filename in examples/hurrtracks.py accordingly. Run hurrtracks.py.

Of course the obvious workaround is not to use . in filenames. But this
is somewhat impracticable as I have a large number or files and would like
keeping the filenames consistent accross filetypes (netCDF, shapfiles,
pngs, etc).

Is there an easy fix?

Thanks very much,

Andy

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/151
.

Sasha

Sasha

[guziy]

I would do smth like this:

if os.path.isfile(shapefile):
(shapeName, ext) = os.path.splitext(shapefile)
else:
shapeName = shapefile

self.shapeName = shapeName

Cheers

2014-04-28 18:44 GMT-04:00 Oleksandr Huziy [email protected]:

I think you are not passing the extension to readshapefile, it is just a
typo in your example, right?

If this is so then the culprit is this line:

https://github.com/matplotlib/basemap/blob/master/lib/mpl_toolkits/basemap/shapefile.py#L249

It is not to hard to fix, so If you want the glory, go ahead) If Jeff
won't mind.

Cheers

2014-04-28 18:31 GMT-04:00 Oleksandr Huziy [email protected]:

Hmm:

I look at the code and do not understand how it worked for you .... What
happens if you don't specify the .shp extension?

Thanks

2014-04-28 18:10 GMT-04:00 Andy Aschwanden [email protected]:

Hi,

(Tested with basemap 1.0.6)

This works:

m.readshapefile('foo.shp', 'my_shape')

while this fails:

m.readshapefile('bar_0.1.shp', 'my_shape')

raise IOError('error reading shapefile %s.shp' % shapefile)
fields = shf.fields
coords = []; attributes = []

IOError: error reading shapefile bar_0.1.shp

Note that foo.shp and bar_0.1.shp are exactly the same file except for
the filename. So it seems that the additional . causes the problem.
Minimal example to reproduce behavior:

Rename huralll020.{shp,dfb,shx} to huralll020_0.1.{shp,dbf,shx} and
change filename in examples/hurrtracks.py accordingly. Run
hurrtracks.py.

Of course the obvious workaround is not to use . in filenames. But this
is somewhat impracticable as I have a large number or files and would like
keeping the filenames consistent accross filetypes (netCDF, shapfiles,
pngs, etc).

Is there an easy fix?

Thanks very much,

Andy

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/151
.

Sasha

Sasha

Sasha

[aaschwanden]

Correct, I realized that basemap does not accept the extension, so my script removes it first, before passing the name to m.readshapfile. The script looks something like this

    shape_filename = ['foo.shp', 'bar_0.1.shp']
    for index, shpfile in enumerate(shape_filename):
        # remove .shp extension
        shpfile = shpfile.split('.shp')[0]
        m.readshapefile(shpfile,
                            'my_shapefile', linewidth=.75)

I'm not an expert python programmer, so this is sort of a hack as it can fail when the filename contains the pattern .shp besides the extension.

[aaschwanden]

@guziy 👍 Yes that should work. I can go ahead and make the code change, if that's ok.

[guziy]

This issue can be closed here, if the issue is still there, then it should be reported to the pyshp project (I am guessing here: https://github.com/GeospatialPython/pyshp).