Computing, GIS and Archaeology in the UK

This is an idea that seems to come up every so often- what GIS programmes can you run from a USB stick. Well it appears that the list has just got longer. I’m probably the last person to realise it’s possible to do this, but I was really pleased to see that both GRASS and PostgreSQL can now be run from a USB stick, along with QGIS, XAMPP (inc Mapserver, OpenLayers, Tilecache), and FWTools.

Before I go any further, I should state that my aims for creating a portable GIS are not so much having a production GIS setup on a stick, because obviously performance and storage are an issue, but it might be useful for demonstration purposes, and I do feel as if the take up of these opensource tools might be more if they were easier to install and came in one handy package. So what I really want to achieve is a single portable package, probably a zip-file, that can be downloaded and unzipped onto a Window pc (they can learn about the joys of linux once we’ve won them over to the basic concept of opensource). No separate downloads, long installation and configuration processes, just a zip file. I do also like having portable packages on my main computer, as if it breaks it’s a lot easier to reconstruct the setup!

The light-bulb moment for me was when Leif told me that he had seen GRASS working on a USB stick using Msys at the recent CAA conference in Berlin. This intrigued me, so I looked into it and it works quite nicely- as long as you use the same drive letter to mount your USB stick to all the time. I still have to figure out how to figure out the drive letter and change the paths, probably in a batch file. Put simply, you download Mingw and Msys onto the stick, follow the instructions for downloading GRASS, edit the install_grass.bat file to change the drive letters, and off it goes.

PostgreSQL was something I had looked into a while ago, been told it wasn’t possible, and given up on. However, the recent 8.2 release appears to have dropped the requirement for a dedicated non-administrative user to run it. If you download the windows binaries, without the installer, you can set it up whilst logged on as the standard user. When you next run PostgreSQL from a different machine, you just have to use the same username as on your installation pc, regardless of whether that user exists on the pc that you are currently using. Once you have PostgreSQL installed, you can install Postgis into the same directory.

Currently there are a couple of gotchas. Most of these programmes require you to set environment variables, which might not be allowed on the particular pc that you are using, and require some command line experience. I still haven’t quite figured out how to get GRASS to work if I change the drive letter. Also, PostgreSQL does indeed run very slowly on a USB stick. And, I haven’t fully explored this to make sure there isn’t a hidden trap somewhere, or security holes that might be exploited. Having said that, if you want a package that can be unzipped onto a pc with a minimum of fuss then I think it’s almost there.

What’s next? Documentation, as always, and the permission of the various programmers that it’s OK to do this. Oh, and comments please, on what else we might include, or words of wisdom if you’ve already tried it.

Archaeogeek is now back in the saddle/desk-chair after a few weeks break- firstly entertaining visiting parents and most recently scuba-diving in the Sound of Mull (Scotland)

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In the mean time I have a few projects coming to fruition, and have been catching up on a few things that I wanted to learn more about (hello google maps and database integration). Firstly, we at Oxford Archaeology have been fortunate to have the services of a very skilled and enthusiastic work-placement student called Matt Jones from the University of Southampton for the last few weeks and he has been helping up get our basic web-based mapping sorted. This collaboration was the first to be arranged via the Antiquist Skills Exchange, where people can post about work they have available, or skills they can offer. It’s still a work in progress to some extent but Matt has done sterling work getting it looking good. Thanks also to Bill Woodall from the OpenLayers mailing list who helped immensely with the ajax code for getting the popups to work nicely.

Secondly, I have been fortunate to have some communication with the MapGuide Open Source development team in terms of getting MGOS working on Ubuntu. This is a long process, made slightly more difficult because of the difference in time zones, but we are making progress, and I am just amazed at them for assigning someone to spend time working with me to get the programme working. I can’t honestly imagine many large companies doing this, and it’s a great credit to the new open mindset at Autodesk. We are currently working through the compilation errors as they occur in the code, and I am taking copious notes so I’ll keep people posted.

Thirdly, Oxford Archaeology’s decision to release our data via wms/wfs is still a matter of debate. Unfortunately for every post or comment that approves of our decision, there is another that tries to figure out what we are gaining financially from the decision. I find this sad, as it’s indicative of a mindset in British Archaeology that we are trying to change. I’m not being naive- we might make some fuzzy and indirect gains from this, and certainly our internal efficiency will improve, but it’s really not the main point- we are making a commitment to the free exchange of data.