Geocoding: From Excel to TileMill (Part II)

Geocoding: From Excel to TileMill (Part II)

This continues from the previous post, where the iPhone GPS data has been batch exported to Excel BUT in a weird DMS format rather than the DD format that we need in order to import into TileMill. Unfortunately, there is no magic button or plugin for this, but in the end… it turns out… its not that hard after all. Doh.

D + M/60 + S/3600 = DD
In Excel:

Note that iPhone’s format may actually be D,M(in decimals) without an S value.

Screen Shot 2012-11-08 at 10.36.40 AM.png
Degree:Minutes:Seconds GPS values converted to Decimal Degrees!
(See Lat and Lon column. TileMill will understand any of the following column headers: latitude, longitude, lat, long,lon, x, y.)

Screen Shot 2012-11-08 at 10.20.00 AM.png

Data successfully imported into TileMill Layer!

Screen Shot 2012-11-08 at 10.44.06 AM.png

Plotted successfully! But what is this? IT IS ALL EMPTY!?????
Screen Shot 2012-11-08 at 10.32.13 AM.png

Oh so I forgot to add in any shape layers. So next we need an ESRI Shapefile for city of Paris available here here and here from and respectively, based on OpenStreetMap data. [See also: Adding Layers in TileMill]

Screen Shot 2012-11-08 at 12.49.08 PM.png
Successful loading of shape layers for buildings and main roads.
Some random slapbang colours here just for testing purposes.


Now I will finetune it from here…