r - Proper points() use in multiples maps with for loop -

i make several maps (one each species of dataset), somehow not able achieve looking for.

i want plot every species record in map, create maps single dot in each one... cannot understand wrong script. me? thank you!

elevation <- getdata("alt", country = "es", mask=f) slope <- terrain(elevation, opt = "slope",neighbors=4)  aspect <- terrain(elevation, opt = "aspect",neighbors=4) hill <- hillshade(slope, aspect, 40, 270) newextent<-extent(-7.99, -2.87, 39.9, 41.5) land.pal <- colorramppalette(c("#336600", "#f3ca89", "#d9a627",                                 "#a49019", "#9f7b0d", "#996600", "#b27676", "#c2b0b0", "#e5e5e5",                                 "#ffffff"), space="lab") (1000)   (i in seq_along(data$species)) {   pdf(file=paste0("map ", data$species[[i]],".pdf"), onefile=f)   plot(disaggregate(crop(elevation,newextent), 1, method="bilinear"), col = land.pal, legend=f)     points(data$lat[[i]],data$long[[i]], col="black") ##the error must here, cannot fix   dev.off() } 

thank in advance

data:

lat long    species -6.99   40.49   sp1 -5.05   40.60   sp1 -3.30   40.02   sp1 -7.51   40.86   sp1 -3.18   40.24   sp1 -3.83   40.08   sp1 -7.28   40.91   sp1 -7.74   40.53   sp1 -7.72   40.69   sp1 -4.36   40.06   sp1 -5.90   40.51   sp2 -5.56   40.07   sp2 -3.52   40.19   sp3 -6.29   40.93   sp3 -6.77   40.12   sp3 -7.11   40.77   sp4 -5.81   40.88   sp4 -5.27   40.68   sp4 -6.31   40.34   sp4 -6.13   40.32   sp4 -6.73   40.99   sp4 -5.32   40.71   sp4 -6.17   40.97   sp4 -4.77   40.92   sp4 -6.45   40.58   sp5 -5.54   40.39   sp5 -6.56   40.66   sp5 -5.27   40.37   sp5 

currently, iterating through every single value of species column , not species whole group , pass 1 point of lat , long, 1 row being passed in for loop.

hence, consider by slice data frame species factor, iteratively passing every sliced data frame function. not shown below by can return named list of objects equal groupings of factor(s) here being species:

by(data, data$species, fun = function(df) {   pdf(file=paste0("map ", df$species[[1]],".pdf"), onefile=false)   plot(disaggregate(crop(elevation,newextent), 1, method="bilinear"), col = land.pal, legend=false)     points(df$lat, df$long, col="black")   dev.off() })