I am using R and tried
Error: could not find function `some.function`
error: could not find function
There are a few things you should check :
install.packages("thePackage")(this only needs to be done once)
library(thePackage)(this should be done every time you start a new R session)
If you're not sure in which package that function is situated, you can do a few things.
??some.functionto get an information box that can tell you in which package it is contained.
getAnywherecan also be used to locate functions.
sospackage as explained in this answer.
RSiteSearch("some.function")or searching with rseek are alternative ways to find the function.