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I can code this, given figures/a formula; but I just flat out don't have the G.I.S knowledge for those figures/formula.

I have to come up with some Python which parses the SRTM elevstion data at 30 arc second resolution, and divide it into (approximately) 1km squares.

I then have to examine each elevation in each square and find the highest point in that square.

I am vague aware that I can't just multiply by a constant to convert - but that's my limit.

How can I divide Europe (the political entity) into roughly km squares using Python?

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You need to convert your lat-long bounding box into a bounding box in a projected coordinate system in metres. You then chop this up into 1,000 unit boxes, giving you kilometre squares.

There are pan-Europe data products that use squares like this, so you might just be able to download a raster with that coverage and get the coordinates of each cell - that's a win especially if you might be overlaying your data with anything else on that system. For example the EU CORINE land cover data uses EPSG:3035 or EPSG:3034 (I forget which) for projections to a metric grid system.

There also appears to be a proposal for a Euro grid system based on one of those CRS: https://en.wikipedia.org/wiki/European_grid

For converting between coordinate systems in Python various solutions exist: How to convert projected coordinates to lat/lon using Python?

Spacedman
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    Yes i think it is customary to use EPSG:3035 while working at the European level. – mgc Sep 26 '16 at 19:52
  • As per http://gis.stackexchange.com/questions/211661/records-of-shapefile-do-not-contain-every-field I have taken the GMTED2010 dataset. We have also chanegd the requirements away from 1km squares and I now just have to find the highest point in each 0.01 degree square, but I don't see that sort of granularity in that file. Time for another question. Please see http://gis.stackexchange.com/questions/212150/granularity-of-elevatin-in-gmted2010-data-understanding-shapefiles – Mawg says reinstate Monica Sep 27 '16 at 14:41