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The ‘dms2dec’ function, posted here a while ago to convert longitude-latitude coordinates from degree-minute-second to decimal format, has recently been updated to accomodate more cases that I and my course participants run into. The function is pasted below and is also available on GitHub, from where it can be sourced directly from R with `source("https://raw.githubusercontent.com/AMBarbosa/unpackaged/master/dms2dec", encoding = "UTF-8")`. Feedback welcome on whether it is working properly!

```dms2dec <- function(dms, separators = c("º", "°", "\'", "’", "’’", "\"", "\'\'", "\\?")) {

# version 1.4 (2 Feb 2022)
# dms: a vector of latitude or longitude in degrees-minutes-seconds-hemisfere, e.g. 41° 34' 10.956" N (with or without spaces)
# separators: the characters that are separating degrees, minutes and seconds in 'dms'; mind these are taken in the order in which they appear and not interpreted individually, i.e. 7'3º will be taken as 7 degrees, 3 minutes! input data are assumed to be properly formatted

dms <- as.character(dms)
dms <- gsub(pattern = " ", replacement = "", x = dms)
for (s in separators) dms <- gsub(pattern = s, replacement = "_splitHere_", x = dms)

splits <- strsplit(dms, split = "_splitHere_")
n <- length(dms)
deg <- min <- sec <- hem <- vector("character", n)

for (i in 1:n) {
deg[i] <- splits[[i]][1]
min[i] <- splits[[i]][2]

if (length(splits[[i]]) < 4) {
hem[i] <- splits[[i]][3]
} else {
sec[i] <- splits[[i]][3]
hem[i] <- splits[[i]][4]
}
}

dec <- colSums(rbind(as.numeric(deg), (as.numeric(min) / 60), (as.numeric(sec) / 3600)), na.rm = TRUE)
sign <- ifelse (hem %in% c("N", "E"), 1, -1)
hem_miss <- which(is.na(hem))
if (length(hem_miss) > 0) {
warning("Hemisphere not specified at position(s) ", hem_miss, ", so the sign of the resulting coordinates may be wrong.")
}
dec <- sign * dec
return(dec)
}  # end dms2dec function```

Usage example:

```    mydata\$lat_dd <- dms2dec(mydata\$lat_dms)

mydata\$lon_dd <- dms2dec(mydata\$lon_dms)```