R has been my environment of choice for plotting spatial data for some time now and this great piece of software got even better with the tmap package.
It easily allow to plot maps such as :
You plot using the function `qtm` and can easily customize the map by providing options to intuitively named subroutines such as tm_fill.
I specially love the different algorithms proposed to choose the classes for the legend, quantiles, k-means … You can simply plot the above with:
where fill simply is the name of the field in the data frame, fill.style is the algorithm used to make the classes of colors and fill.palette the name of the pallette that can be checked up using :
Check up the help for tm_fill to understand the fill.xxx parameters!
Two thumbs up for tmap!!!
Wednesday, May 8th was the official release date for the report on access to primary care in Philadelphia.
We’ve got some nice coverage of our study by the LDI periodical of course but also by NewsWorks and Philly.com (Philadelphia Inquirer).
For quick and easy cartography, “My maps” service from Google allows to make and publish online maps.
A csv with coordinates can easily be uploaded. It also supports drawing of points, polygons and polylines on multiple layers.
Maps are easily modifiable using a smartphone: a must have for field cartography
Note that the export format is kml/kmz. The kmz exported can be unzipped with any zipping utility returning a kml. The kml can be imported directly in R using readOGR in the the rgdal package. It can also be imported in QGIS and from there exported to many formats.
This significant expertise on the access to primary care in the Philadelphia, PA involved several of our key know-how:
- Data Management with merging of practitioners and population information from over 10 data sources
- Spatial analysis based on driving distances
- Cartography with the constitution of interactive Google maps involving spatial statistics under the hood
- Web development to interface the whole
It is reaching an end with the recent delivery of the review report.
Our next steps are to:
- Make available online the interactive map engine, without proprietary data
- Publish in medical journals the key findings of the study (yes, access to care has social determinants…)
We will keep you posted.