Computing, GIS and Archaeology in the UK

The event visualisation plugin for QGIS is a way of adding tabular geographic data to QGIS in a similar way to the “add XY data from table” option in ArcGIS. I’ve only tried the windows version so far but it is cross-platform.

You download it from here

Extract the zip file and move the files to the following locations:

• Copy plugins/libevis.dll to C:\Program Files\Quantum GIS\plugins
• Copy the imageformats folder to C:\Program Files\Quantum GIS
• Copy the sqldrivers folder to C:\Program Files\Quantum GIS

Ensure the plugin is installed and activated by checking plugins\plugin manager in QGIS, and ticking the checkbox next to EVIS. If it is not present then you haven’t installed it correctly.
In plugins/eVIS choose the data connection option.
Choose access as the database type, and browse to the database in the database name box.
Hit the “connect” button to test the connection.
In the SQL query tab, type the SQL query that defines the data that you want. If you don’t know how to write SQL, make the query in access and choose the SQL View, then copy the query into QGIS. If you want to display the data from one table, then the syntax is “select * from your_table”.
Once you have the right query, hit the “run query” button.
Choose a name for your layer, and choose the fields that represent the x and y coordinates for your data.
Click “OK” to see the data displayed on the map

Never apologise for delayed posts… this is a Sunday Tip Day post, not a Thursday! Anyhow…

I just found a super little cross-platform utility that takes shapefiles and dumps them to a variety of text-based formats. Download it here, and simply unzip it to use it.

There isn’t much documentation, but basically your options are to download to gpx or spreadsheet. The following gives you a simple delimited text file with the coordinates and values from your attribute table:

./shp2text -–spreadsheet /path/to/your/shapefile.shp > /path/to/output.txt

Bob is indeed your mother’s brother.

Time for a quick catch up…

Last Thursday was the first get-together for the UK OSGeo local chapter. Actually we’re not a formal chapter yet- we have to get approved by the board first but it’s a start! People came along from a wide variety of different GIS sub-disciplines, which was nice, although there was a comment that perhaps archaeology was over-represented! We had a selection of quick talks from Tyler Mitchell (intro to OSGeo), Suchith Anand (OGC Interoperability), me (Portable GIS) and Jason Jorgenson (FOSS for archaeological site catchment analysis), and then had a lively discussion about what we thought the local chapter should do.

Various channels were suggested for promoting the chapter and providing forums for meeting up (important for continuing the momentum), and there were many good ideas for what it should actually do. In general people felt that a local chapter could provide a “professional face” for the use of open source software, making links with the big industry players within the UK, like the AGI (Association for Geographic Information). Rather than “going up against” the proprietary companies, we should be highlighting the fact that there is a viable choice.

This is a big ask in a way. Holding informal seminars on the back of conferences is one thing, but providing a professional face means creating literature and display material and attending as many of the large industrial conferences as possible. I’m not sure how that’s going to play out as we’ll be relying on the goodwill and enthusiasm of volunteers, but we’ll see how it goes. I might sound a little down-beat about it, but I don’t mean to- it’s exciting stuff- or has the potential to be.

Our next step is to get the mailing list of the ground, to get people talking. Then we are hoping to have a presence in some fashion at the Geospatial Web Services workshop at the University of Nottingham in June. Then the AGI conference is in September, and FOSS4G is after that… the world is our oyster (or should that be fish and chips for us Brits?)

Just as we are settling down with the transition to open source, it would seem that a lot of other people are at least considering their options along the same lines, for whatever reason. This thread on the osgeo_discuss list, started off as a question about the value of open source to individual’s careers, but rapidly morphed into a discussion about replacing the ESRI packages. This seems to have lead to a general consensus about the areas where the open source packages do well and do badly.

The consensus seems to be that the open source packages are great for the behind-the-scenes and/or web-based work, assuming a relatively technically literate user, but that cartographic capabilities are sadly lacking at the moment. Furthermore, if you’re looking for one single replacement, then you’re out of luck- but you can assemble a toolkit that will get you all the capabilities you need, in a modular fashion. This does require a change in mindset- but it’s a lot more flexible and hopefully more powerful.

I hope that this recent upswell of interest and consensus about where the open source packages need improvement will help focus development in those areas. This does seem to be happening: this page is about plans for a cartographic library that can be shared amongst different packages. Sign up to show your support!

PS- if you’re in the UK you can still come along to our first UK OSGeo meetup at Stansted tomorrow (Thursday 1st) at 4.30. It’s free to attend, there will be some talks to start with (better finish writing mine), then we’ll sit down and try and figure out what we want a UK local chapter to do. There will be tea, coffee and biscuits too, so what are you waiting for!