How long does [insert code snippet] take in Python? Find out with the timeit module, in Python since 2.3. Below I time how long it takes to make a list with a 1000 zeros, [0,0,0,…], using different Python code snippets.…
pyproj is a Python interface to the PROJ.4 () functions. It allows you to transform coordinates between coordinate systems. Install pyproj using pip Assuming you’re using pip to install Python packages: $ pip install pyproj
I tried the Tor browser today, and was amazed at how slow it was. As Tor’s user base has grown, the performance of the Tor network has suffered. This document describes the current understanding of why Tor is slow, and…
The recommended practice is to have different passwords on different websites. But how do you remember all those passwords without storing them somewhere? The tricks is, you don’t. You remember a single strong password, and use a mechanism to generate…
Note: Since writing this post, I’ve learned about the fileinput module, which turns most of the following into a oneliner: import fileinput for line in fileinput.input(): process(line)
In this post I’ll compare the running time of reading uncompressed and compressed files from disc. I’ll run a test using two files, data.txt (858M) and data.txt.gz (83M), that have the same content. About cat and zcat The well-known command…
Here is a map application that illustrates very well the different tile schemes used (TMS, QuadTree, Google Maps):
Online documentation for GDAL/OGR Python is sparse. Here I show some recommended ways of learning more about GDAL/OGR in Python. Using Python interpreter You can learn about GDAL and OGR from inside the Python interpreter. Start python interpreter: $ python…
GDAL is not very well documented, and a complete Python API documentation site is not something I’ve found. So here are the best tutorials I’ve found so far for GDAL + Python. GDAL Python samples on osgeo.org
Simple CSV file import You have a CSV file called “data.csv”. It has a header line, and is delimited using “;”. You want to import it into Postgres and a table called “your_table”: Create the database table. Set column-types so…