R/gr_det_country.R

In BiologicalRecordsCentre/sparta: Trend Analysis for Unstructured Data

gr_det_country <-
function(gridref){
  # Create variable to store output
  cty_out = rep(NA, length(gridref))
  
  # Find British Gridrefs
  cty_out[grepl('^[[:upper:]]{2}[[:digit:]]{2,}$',gridref) & !grepl('^(WA)|(WV)[[:digit:]]{2,}$',gridref)] = "OSGB"
  
  # Find Irish Gridrefs
  cty_out[grepl('^[[:upper:]]{1}[[:digit:]]{2,}$',gridref)] = "OSNI"
  
  # Find Channel Islands Gridrefs
  cty_out[grepl('^(WA)|(WV)[[:digit:]]{2,}$',gridref)] = "UTM30"
  
  # Return output object
  return(cty_out)
}