swcEcon 0.1.0
First CRAN release
New functions (16 exported)
calc_bcr() – Benefit-cost ratio with discounting,
benefit lag, residual value.
calc_npv() – Net present value with annual cash-flow
table.
calc_irr() – Internal rate of return via bisection
(Brent 1973).
calc_pbp() – Simple and discounted payback period.
calc_mrr() – Marginal rate of return (CIMMYT
1988).
calc_mbcr() – Modified benefit-cost ratio (Gittinger
1982).
calc_soil_loss_cost() – USLE-based soil loss economic
valuation.
calc_nutrient_cost() – NPK replacement cost from
erosion.
calc_water_value() – Groundwater recharge and runoff
harvesting value.
calc_irrigation_benefit() – Additional crop income from
SWC-enabled irrigation.
calc_employment() – Employment generation ratio with
MGNREGS norm check.
sensitivity_analysis() – One-at-a-time sensitivity
analysis (8 scenarios).
calc_switching_value() – Switching value for cost and
benefit.
monte_carlo_swc() – Stochastic BCR/NPV simulation
(Pouliquen 1970).
run_swc_pipeline() – Full appraisal pipeline in one
call.
generate_swc_report() – Self-contained HTML economic
appraisal report.
Datasets (6)
swc_benchmarks – Real: NABARD WDF Reports 2010-2022;
PMKSY-WDC (GoI).
usle_india_soils – Real: NBSS and LUP Technical
Bulletin 132 (ICAR).
rainfall_erosivity_india – Real: IMD + Bhattacharyya et
al. (2010).
swc_cost_norms – Real: PMKSY-WDC Common Guidelines (GoI
2015).
watershed_projects – Hypothetical: set.seed(2025), 50
projects.
farmer_adoption – Hypothetical: set.seed(2025), 120
households.
Technical notes
- All source files are pure ASCII – CRAN portable.
- Dataset documentation uses NULL sentinel pattern for roxygen2
compatibility.
- Zero runtime dependencies beyond base R (stats, graphics, grDevices,
utils).
markdown = FALSE in DESCRIPTION – plain Rd syntax
throughout.