Own exercises in actinia
Meanwhile you have seen a lot of material. Time to try out some further exercises...
1. What is the altitude of the highest point in North Carolina? Check it with actinia.
- Find the correct raster in the North Carolina location and PERMANENT mapset.
- Find the relevant raster layer by rendering it
- Print the information and get altitude of the highest point
2. Find the zipcode in Wake county with the most hospitals
- Find the relevant vector layers
- Check the zipcode vector layer for the relevant column to get the zipcode
- Create a process chain as a .json file to ask for the number of hospitals in the zipcodes: Use the GRASS GIS modules
g.copy
(because you are not allowed to change data from an other mapset),v.vect.stats
andv.db.select
- Post the created process chain to
https://actinia.mundialis.de/api/v3/locations/nc_spm_08/processing_async
for ephemeral processing
3. Export the water bodies from the available Landsat imagery of North Carolina
- Create a process chain as a .json file
- Remember to set the computational region
- Compute the NDWI (Normalized difference water index); use
r.mapcalc
ori.vi
- Filter water bodies by a threshold of e.g. 0.35 using
r.mapcalc
- Either export the water bodies (use the
exporter
with the ephemeral processing) or render the maps of NDWI and water bodies with a nice color (user.colors
and persistent processing in your own mapset)
4. Population at risk near coastal areas
- needed geodata:
- Worldwide SRTM 30m (already available in actinia as
srtmgl1_v003_30m
- find out the location yourself) - South America Population 2015 (already available in actinia as
worldpop_2015_1km_aggregated_UNadj
- find out the location yourself) - raster shorelines (already available in actinia as
ne_1000m_coastlines
- find out the location yourself)
- Worldwide SRTM 30m (already available in actinia as
- fetch metadata with actinia interface and render input data
- proposed workflow:
- set computational region to a small subregion (hint:
align
the region resolution to the population raster) and check the pixel number against user constraints - buffer the coastlines by 5000 m and set a mask to the result
- Extract only the peopulation below 10 m
- Calculate the statistic to get the population at risk near coastal areas
- set computational region to a small subregion (hint:
- Hints for example GRASS modules to use in process chain:
g.region
,r.buffer
,r.mapcalc
,r.mask
,r.univar