Thinking Big with Maps in R
Tips on Wrangling Large Vector Data into Interactive Maps
Silvia Canelón, PhD
CANSSI Ontario Statistical Software Conference
Nov. 10, 2022
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Silvia Canelón
Data Analyst @ Penn Urban Health Lab
University of Pennsylvania, Philadelphia, PA, US
silviacanelon.com
fosstodon.org/@spcanelon
@spcanelon
@spcanelon
Static map
Plotting with geom_sf()
- A lot of lines
- Some large polygons?
- Seems like the entire county was covered by tree canopy
I needed an interactive map to take a closer look at the data
Which package to use?
leafletis best for datasets with <50,000 features…my tree canopy dataset had 193,418 multipolygonsleafglis recommended in concert withleaflet(spoiler: it didn’t work for me)- settled on
mapview
Plotting with mapview
- Vertical strips of data missing
- Non-functional interactivity
- RStudio would crash
- VSCode was hit-or-miss
QGIS rendering
in action
Suggestion
Simplify geometry with rmapshaper
- super complicated multipolygons
- simplifying eliminating features
- but it could!
Suggestion
Try the tmap package
Suggestion (WIP)
Try the rdeck package
Thank you #RStats!
Bonus slide!
This slide was added after the presentation to include feedback from talk attendees
- Rendering issues might come from maxing out the RAM
- To reduce the size of the dataset, one could adjust the precision because sometimes the features contain more digits than you need or can meaningfully rely on
- The mapdeck package might be another one to try. It’s powerful and sits on Mapbox which lets you pull in nice basemaps as well
Silvia Canelón
silviacanelon.com
fosstodon.org/@spcanelon
@spcanelon
@spcanelon
Thinking Big with Maps in R Tips on Wrangling Large Vector Data into Interactive Maps Silvia Canelón, PhD CANSSI Ontario Statistical Software Conference Nov. 10, 2022