Saturday, 10 May 2014

Handy maps

A 'handy' is what Germans call a mobile or cell phone. I uploaded free ArcGIS for Android on my  smartphone, which now has a decent screen to read maps on - love my Navigon Europe on it, and Google Maps too - but here is a quick&easy application of arcgis.com for the rest of us. 

With the European elections coming up, I canvass my neighbourhood for the French UDF party. As a French resident in the UK I voted for local councils and European parliament, but now expats have direct representation in the Consulate and indirect in the National Assembly. Canvassing my neighbourhood is a classic traveling salesman problem, that is: where are my compatriots and how can I best reach them?

The electoral list I received from the French Consulate is confidential of course. What is shown below is what I carry around on my smartphone to canvass, but not to share online. Here is what I did to achieve this:
  • cleaned up the electorate file to have name, address, postcode and email in neat columns (you will not believe how such data are kept and circulated, I suppose it's how people entered it in the first place)
  • uploaded the CSV file to arcgis.com which then geocoded the post codes, but kept it private
    (previous post on rail station use noted post code area as the smallest geo entity freely available)

    click image to enlarge 

But in order to share this with you, here are further steps I took:
  • downloaded the postcode area as KML and converted it to a shape file
  • downloaded the Ordnance Survey VectorMap District - TL for my post code
  • projected them same as arcgis.com, and clipped them to the postcode area
  • stripped the file to show geo (street, town) but not private (name, postcode) data
  • uploaded all  files to arcgis.com et voilà! remember to click on them for pop-ups
  • note that the size of the address symbol makes it selectable on the smartphone


View Larger Map

So DIY maps are as easy as... 
  1. load a spreadsheet to geocode quickly&easily on arcgis.com
  2. read it on my smartphone to help me canvass my neighbourhood
  3. clean it and strip it of any secure info to share publicly and freely  
[Update1: see the social map created from this on a custom arcgis.com account.
Update 2: see the traveling salesman problem executed for the post code area.
Update 3: see the traveling salesman problem executed for just a portion of it.]