open #1, "manipy.csv", "r" //existing CSV file separated by spaces, not commas
open #2, "manip2.csv", "w" //new CSV file for writing changed data

line input #1 header$
header$ = header$ + ",SUM"
print #2 header$

while !eof(1)
    input #1 c1, c2, c3, c4, c5
    sum = c1 + c2 + c3 + c4 + c5
    print #2 c1, c2, c3, c4, c5, sum
wend

close #1
close #2
end