intersect_points: Intersect environmental or contextual layers at a given a set...

In fozy81/NBN4R: National Biodiversity Network Atlas (UK and Ireland) Data and Resources in R

Description

Intersect environmental or contextual layers at a given a set of points (coordinates)

Usage

intersect_points(pnts, layers, SPdata.frame = FALSE, use_layer_names = TRUE,
  verbose = nbn_config()$verbose)

Arguments

pnts	numeric: vector of latitude/longitude pairs, or a 2 column data.frame or matrix of lat,lons. NOTE: the number of locations must be less than 1000.
layers	string vector: ids of layers to be intersected. The list of possible layers is available from nbn_fields("layers"). Names can be passed as full layer names (e.g. "Radiation - lowest period (Bio22)") rather than id ("el871"). Note: if more than one location has been provided in pnts, the number of layers must be less than 700.
SPdata.frame	logical: should the output should be returned as a SpatialPointsDataFrame of the sp package or simply as a data.frame?
use_layer_names	logical: if TRUE, layer names will be used as column names in the returned data frame (e.g. "radiationLowestPeriodBio22"). Otherwise, layer id value will be used for column names (e.g. "el871")
verbose	logical: show additional progress information? [default is set by nbn_config]

Value

A SpatialPointsDataFrame containing the intersecting data information. Missing data or incorrectly identified layer id values will result in NA data

References

The associated NBN web service: https://api.nbnatlas.org/#ws84

Descriptions of the spatial layers: https://layers.nbnatlas.org/layers/

This function allows the user to sample environmental/contextual layers at arbitrary locations. It complements the occurrences function, which allows values of the same set of layers to be downloaded at species occurrence locations. NOTE: batch requests (multiple points) are currently processed in a *single queue* on the NBN servers. Processing times may be slow if there are many requests in the queue. Note also that the actual processing of batch requests is inherently slow: a large number of points may take quite some time. Be warned.

See Also

nbn_config

Examples

## Not run: 
 # single point with multiple layers
 # i.e local environmental Records Centre boundaries UK &
 # watsonian vice counties:
 layers <- c('cl23','cl14')
 pnts <- c(51.5074,0.1278)
 intersect_points(pnts,layers) 
 # equivalent direct web service call:
 # https://layers.nbnatlas.org/ws/intersect/cl23,cl14/51.5074/0.1278  

 # multiple points as a grid sampling multiple layers
 # i.e ancient woodland & watsonian vice counties:
 layers <- c('cl23','cl14')   
 pnts <- data.frame(expand.grid(lat=seq(51.5074,52.5074),lon=seq(0.1278,0.1278)))
 intersect_points(pnts,layers)

## End(Not run)

fozy81/NBN4R documentation built on May 19, 2019, 8:22 a.m.