sum() with raster::aggregate() in R

If you try to use sum() directly in raster::aggregate() and have NA values, you’ll get NA as a result. You need to build a tiny function and pass the rm.na=T command to sum(). More succintly:

# Dissolve duplicate geometries and sum OOIP
 fm <- raster::aggregate(fm.raw,
                         by="OilFieldID", 
                         sums=list(list(function(x) sum(x,na.rm=T),
                                        "OOIP_pooltable")))

 

Comparing two lists with R

No, not list() lists.

a <- data.frame(name=old$NAME)
a$status <- "old"
b <- data.frame(name=allfields[allfields$StateAbbre=="ND",]$name)
b$status <- "new"

both<-merge(a,b,by="name",all=T)

Make two data frames, one for each list, create a column identifying each one (new or old), then join on the common column (name).

Output:

Example output from comparing to lists in R using a merge().
Example output from comparing to lists in R using a merge().

See also: http://stackoverflow.com/questions/17598134/compare-two-lists-in-r/17599048#17599048