suggest_top_crs {crsuggest}

Return the CRS code for a "best-fit" projected coordinate reference system

Description

Return the EPSG code or proj4string syntax for the top-ranking projected coordinate reference system returned by suggest_crs(). This function should be used with caution and is recommended for interactive work rather than in production data pipelines.

Usage

suggest_top_crs(input, units = NULL, inherit_gcs = TRUE, output = "epsg")

Arguments

input

An input spatial dataset of class "sf", "Spatial*", or "RasterLayer".

units

(optional) The measurement units used by the returned coordinate reference system.

inherit_gcs

if TRUE (the default), the function will return a CRS suggestion that uses the geographic coordinate system of the input layer. Otherwise, the output may use a different geographic coordinate system from the input.

output

one of "epsg", for the EPSG code, or "proj4string", for the proj4string syntax.

Value

The EPSG code or proj4string for the output coordinate reference system.

Examples

## Not run: 

# Let's say we are working with a demographic dataset from the US Census:
library(tidycensus)
library(ggplot2)
library(sf)
library(crsuggest)

tx_income <- get_acs(
  geography = "county",
  variables = "B19013_001",
  state = "TX",
  geometry = TRUE
)

# We can use `suggest_top_crs()` to return the EPSG code of the "top" suggested CRS
# for statewide mapping of Texas
tx_crs <- suggest_top_crs(tx_income)

# The returned CRS is EPSG code 3083, NAD83 / Texas Centric Albers Equal Area.
# This code can be used for visualization:

ggplot(tx_income, aes(fill = estimate)) +
  geom_sf() +
  coord_sf(crs = tx_crs)

# Alternatively, we can transform the CRS of our sf object directly:

tx_projected <- st_transform(tx_income, tx_crs)

## End(Not run)