A RasterStack containing travel time isochrones for 77 hospitals in Thailand's Region 12. Each layer represents the travel time (in minutes) to reach one hospital, computed using the OSRM (Open Source Routing Machine) routing engine.
**Note**: As of version 0.2.4, this dataset has been moved to external data storage to improve package performance. The data is no longer lazy-loaded, so direct usage like `rast(hos_iscr)` is not supported. Please use `read_spax_example("hos_iscr.tif")` to access this dataset.
Format
A GeoTIFF file containing a multi-layer raster with:
- Dimensions
509 rows × 647 columns × 77 layers
- Resolution
520.4038 × 520.4038 meters
- Extent
505646.5, 842347.8, 620843.7, 885729.2 (xmin, xmax, ymin, ymax)
- CRS
WGS 84 / UTM zone 47N (EPSG:32647)
- Values
Travel time in minutes
- Layer Names
Match facility IDs in hc12_hos (e.g., "c172", "c173")
Source
Computed using OSRM with OpenStreetMap data.
Hospital locations from hc12_hos.
Details
Travel times were calculated using the following time-break structure:
1-minute intervals for first 10 minutes
2-minute intervals from 12 to 30 minutes
5-minute intervals from 35 to 60 minutes
15-minute intervals from 75 to 180 minutes
References
Luxen, D., & Vetter, C. (2011). Real-time routing with OpenStreetMap data. In Proceedings of the 19th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems (pp. 513-516).
Examples
if (FALSE) { # \dontrun{
# Old method (no longer supported):
# rast(hos_iscr) # Will not work after v0.2.4
# New method:
hos_iscr <- read_spax_example("hos_iscr.tif")
# Plot travel time to first hospital
plot(hos_iscr[[1]], main = "Travel Time to First Hospital (minutes)")
} # }