disambiguate_indexes | R Documentation |
Given a set of flowline indexes and numeric or ascii criteria,
return closest match. If numeric criteria are used, the minimum difference
in the numeric attribute is used for disambiguation. If ascii criteria are used,
the adist function is used with the following algorithm:
1 - adist_score / max_string_length
. Comparisons ignore case.
disambiguate_indexes(indexes, flowpath, hydro_location)
indexes |
data.frame as output from index_points_to_lines with more than one hydrologic location per indexed point. |
flowpath |
data.frame with two columns. The first should join to the id field of the indexes and the second should be the numeric or ascii metric such as drainage area or Name. Names of this data.frame are not used. |
hydro_location |
data.frame with two columns. The first should join to the id field of the indexes and the second should be the numeric or ascii metric such as drainage area or GNIS Name. Names of this data.frame are not used. |
data.frame indexes deduplicated according to the minimum difference between the values in the metric columns. If two or more result in the same "minimum" value, duplicates will be returned.
if(require(nhdplusTools)) {
source(system.file("extdata", "sample_flines.R", package = "nhdplusTools"))
hydro_location <- sf::st_sf(id = c(1, 2, 3),
geom = sf::st_sfc(list(sf::st_point(c(-76.86934, 39.49328)),
sf::st_point(c(-76.91711, 39.40884)),
sf::st_point(c(-76.88081, 39.36354))),
crs = 4326),
totda = c(23.6, 7.3, 427.9),
nameid = c("Patapsco", "", "Falls Run River"))
indexes <- index_points_to_lines(sample_flines,
hydro_location,
search_radius = units::set_units(0.2, "degrees"),
max_matches = 10)
disambiguate_indexes(indexes,
dplyr::select(sample_flines, COMID, TotDASqKM),
dplyr::select(hydro_location, id, totda))
result <- disambiguate_indexes(indexes,
dplyr::select(sample_flines, COMID, GNIS_NAME),
dplyr::select(hydro_location, id, nameid))
result[result$point_id == 1, ]
result[result$point_id == 2, ]
result[result$point_id == 3, ]
}
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