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SPEI (R package)
StableThe reference R implementation of SPEI and SPI from the index's own authors.
- Pricing
- Open Source
- License
- GPL-2+
- Commercial use
- Permitted
- Ecosystem
- R
- Platform
- Windows, macOS, Linux
Install
install.packages("SPEI")About SPEI (R package)
The SPEI package is maintained by Santiago Beguería — co-author of the Standardised Precipitation-Evapotranspiration Index itself — making it the closest thing to a canonical implementation. It computes SPEI and SPI at any timescale, with the PET routines (Thornthwaite, Hargreaves, Penman-Monteith) the index depends on, and kernel-weighting and distribution options documented against the original papers.
For drought analyses that will be reviewed, "computed with the authors' own package" is a satisfying provenance line. Simple API, stable on CRAN, widely cited.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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