Someone has asked the best way to display information related to a postcode on a map. I thought I would blog this as it is a common issue I am asked about.
There are a number of ways, each with their own strengths and weaknesses. However, in my opinion, the best (and cheapest, assuming you can abide with the Google Fusion Table licence) non-programming way is to use Google Fusion Tables. I am a big fan of Google Fusion Tables – see my previous blog post here.
My example of a postcode based fusion table map.
Google Fusion Tables allow you to import data from Excel and, assuming it has location data in it, then you can display it on a map. Google have some great examples of how to do this with a video here and a step by step guide here.
I have also produced a simple map from this data and shared it for you so see what is possible. A picture of the map is shown on the right so you know what to expect.
A few pointers from me on Fusion Tables
The Google information is great but here are a few things that you might save you some time.
- Import: You can import straight from Excel but it doesn’t handle columns with formulas, which has caused me problems in the past (they may have fixed that). Therefore I normally import from CSV (comma separated values) files.
- Consider using lat/long: If you supply postcodes then you a) need to tell Google which of your columns holds the postcode and b) it has to go through a geocoding step. If you are updating the data a lot then this adds extra steps and takes time. I therefore recommend supplying latitude and longitude data instead of postcodes. Google will automatically set columns called ‘latitude’ and’ longitude’ as the location columns and it doesn’t need to go through the geocoding process.
– Free Postcode to Latitude and Longitude data is available via data.gov.uk here but it gives the coordinates in Northings and Eastings, not lat/long. However someone at www.doogal.co.uk has very helpfully converted the list to include latitude and longitude – see this link here (note the file is very large)
- Dynamic Icons: I find the default icon not very useful and I set map configuration to select the icon using a column in your data. This gives me full control of what icon appears where. There are lots of different icons – see here for a map showing all the icons (click on an icon to see its name).
- Sharing: With the free licence your data is either private to you or publicly available (but can be hidden), i.e. you can’t share it with a few people privately. What I normally do is share it with the option ‘Anyone with the link’, which means that search engines won’t find it but people can access it if they want. Please read the Google Fusion Table licence for the specifics of what you are allowed to do.
I hope this helps everybody. Feel free to ask questions on my blog and I will try to get back to you with answers.