[okfn-discuss] Open topological data

Sat Dec 20 15:02:56 UTC 2008

On Fri, Dec 19, 2008 at 09:49:04AM +0000, Rufus Pollock wrote:
> If so the most immediate item that comes to mind is the topography
> data from the SRTM:

> http://www.ckan.net/package/read/geo-srtm

That's fantastic, exactly what I needed.

> That data is public domain (from NASA) and available via ftp. However
> quite large and in fairly raw form so may need some processing

numpy make it trivial to do: the NASA docs say it is raw data made of signed 
two byte integers, on a grid of shape 3601x3601, in other words:

    import numpy as np
    data = np.fromfile('N36W113.hgt', '>i2')
    data.shape = (3601, 3601)

> If this isn't suitable take a look through packages on CKAN tagged
> with geo or geodata:

> <http://www.ckan.net/tag/read/geo>
> <http://www.ckan.net/tag/read/geodata>

> Or just search packages generally:

> <http://www.ckan.net/package/search>

CKAN is great. I need nice datasets for examples with Mayavi, I think
I'll find a lot of inspiration. Thanks for the tip, I should have thought
about CKAN.

Gaël