Performs the same type of operation as block2prec, but subsets a precinct geometry based on a County fips column. This helps get around the problem that county geometries often have borders that follow rivers and lead to funny shaped blocks. This guarantees that every block is matched to a precinct which is in the same county.
block2prec_by_county(block_table, precinct, precinct_county_fips, epsg = 3857)Required. Block table output from create_block_table
sf dataframe of shapefiles to match to.
Column within precincts
numeric EPSG code to planarize to. Default is 3857.
dataframe with nrow(precinct) rows
if (FALSE) {
# Need Census API
data(towns)
towns$fips <- '087'
block <- create_block_table('NY', 'Rockland')
block2prec_by_county(block, towns, 'fips')
}