---
title: "Introduction to sdc.redistribute"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Introduction to sdc.redistribute}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

```{r setup}
library(sdc.redistribute)
```

`sdc.redistribute` moves measured values from a *source* set of polygons onto a
*target* set that does not share the same boundaries.

```{r}
library(sdc.redistribute)
data(sdc_example)

# Area-weighted: split tract population onto neighborhoods.
redistribute_direct(sdc_example$source, sdc_example$target, extensive = "pop")

# Dasymetric: weight the split by parcels (here, by unit count).
redistribute_parcels(
  sdc_example$source, sdc_example$target, sdc_example$parcels,
  extensive = "pop", weights = "units")
```

Use `extensive` for counts (totals are preserved) and `intensive` for rates
(area-weighted means).