string split

fullString="1,5,10"

function splitString(sourceString,splittingChar,index)
    for i=1,index do
        start,stop=string.find(sourceString,splittingChar)
        if start==nil then
            start=string.len(sourceString)+1
            stop=start
        end
        splittedString=string.sub(sourceString,0,start-1)
        sourceString=string.sub(sourceString,stop+1,string.len(sourceString))
    end
    return splittedString
end

print(splitString(fullString,",",3))