Exegesis Spatial Data Management


Posts in Category: Python

How to remove .png files recursively from a folder tree without removing .png8 files too

We have some large GeoWebCache caches of Ordnance Survey map tiles in .png8 format. Unfortunately a few million .png files have crept into the caches too (accidental bad config at some point),... read more

Find "Godzillas" in your ArcGIS feature class (by counting vertices)

A useful way to select and generalise only the more complex features
To count the number of vertices: Add a new field to the feature class called, for example, VertexCount Use the Calculate Field tool within the attribute table, or in ArcToolbox, with the... read more

Tilecache: how to stop tilecache_seed.py bailing out with HTTP 502 errors

We are using TileCache http://tilecache.org/ to create caches of Ordnance Survey data of various flavours, for use in high demand web sites. We are tending to pre-seed the caches, then access them... read more

Serving Ordnance Survey rasters with GeoServer and MapServer - some irks and quirks

I’ve been preparing a tilecache of UK Ordnance Survey mapping for a couple of big projects, combining Open Data with licensed Landranger (1:50,000) and Explorer (1:25,000) mapping. The tilecache... read more

Breaking a site with Multi-Mechanize

In my previous post I got started with Multi-Mechanize and established that it is a useful tool for load-testing web sites. Next I tried it on a real site that we are currently building – the new... read more

Trying out Multi-Mechanize web performance and load testing framework

Information and download from http://code.google.com/p/multi-mechanize/ UPDATE 14th March 2012: now moved to http://testutils.org/multi-mechanize Multi-Mechanize is an open source... read more