A function to retrieve the definitions for one or more geologic map sources in the Macrostrat database. By default, all source definitions are returned.
Usage
def_sources(
source_id = NULL,
lat = NULL,
lng = NULL,
shape = NULL,
buffer = NULL,
scale = NULL,
sf = TRUE
)
Arguments
- source_id
integer
. The unique identification number(s) of the desired source(s) to return a definition for.- lat
numeric
. A valid latitude in decimal degrees to return a source definition for. Must also supplylng
.- lng
numeric
. A valid longitude in decimal degrees to return a source definition for. Must also supplylat
.- shape
character
. A valid well-known text (WKT) representation of geometry, such as "POINT(30 10)" or "POLYGON((30 10, 40 40, 20 40, 10 20))", to return a source definition for.- buffer
integer
. The geographic buffer (in meters) that should be applied to the specifiedshape
.- scale
character
. The desired Burwell scale, either: "tiny" (global), "small" (continental), "medium" (regional), or "large" (local).- sf
logical
. Should the results be returned as ansf
object? Defaults toTRUE
. IfFALSE
, adata.frame
is returned.
Value
A data.frame
containing the following columns:
source_id
: Identification number of the geologic map source.name
: Name of the geologic map source.url
: URL where additional information, the source, or contributing publication can be found.ref_title
: Title of reference for geologic map source.authors
: Authors of geologic map source.ref_year
: Year of reference publication.ref_source
: Original publication source of the reference.isbn_doi
: The ISBN or DOI for the reference.scale
: The Macrostrat scale the geologic map source belongs to.features
: The total number of features (i.e., outcrop shape and point elements) associated with the geologic map source.area
: The total geographic area of the geologic map source in km2.
If sf
is TRUE
(the default), an sf
object is returned instead, with
the same columns plus a "geometry" column that contains the spatial data.
See also
Geologic maps:
get_map_legends()
,
get_map_outcrop()
,
get_map_points()
Macrostrat database metadata:
def_projects()
,
def_references()
,
get_stats()
Examples
# \donttest{
# Get all sources
ex1 <- def_sources()
# Get subset of sources
ex2 <- def_sources(source_id = c(1,2,4))
ex3 <- def_sources(lat = 43.03, lng = -89.4, scale = "large")
# Use WKT representation
library(sf)
#> Linking to GEOS 3.10.2, GDAL 3.4.1, PROJ 8.2.1; sf_use_s2() is TRUE
line <- st_linestring(x = matrix(c(-122.3438, 37,-89.3527, 43.0582),
byrow = TRUE, ncol = 2))
ex4 <- def_sources(shape = st_as_text(line), buffer = 100)
# }