Sum part of row and add this as a new column vector

[Peterso]

County 1990 1991 1992 1993
Alachua 1 1 1 1
Baker 0 0 0 0
Bay 0 0 1 0
Bradford 0 0 0 0


I would like to add up all the scores for each year and add it as a new Total column. I tried to use matrix functions, they they assume all data is numeric. I need to add only from column 2 to n. It should look like the table below.

Johnny

County 1990 1991 1992 1993   Total
Alachua 1 1 1 1              4
Baker 0 0 0 0              0
Bay 0 0 1 0              1
Bradford 0 0 0 0              0

[Rui Barradas]

Hello,

Try

df1 <- read.table(text="
County 1990 1991 1992 1993
Alachua 1 1 1 1
Baker 0 0 0 0
Bay 0 0 1 0
Bradford 0 0 0 0
", header=TRUE)

df1$Total <- rowSums(df1[ , -1]) # Not column 1
df1$Total <- rowSums(df1[ , 2:5])# Explicit column numbers

Hope this helps,
Rui Barradas

[Peterso]

Everything is simple when you know what you're doing.

Thanks, it worked exactly as I wanted it.
 Johnny

[Indrajit Sen Gupta]

You can the "apply" function to compute like this:

dt <- read.table("peter.txt", header = TRUE)

total <- apply(X= dt[,2:5], MARGIN = 1, FUN = sum)

final <- cbind(dt, total)

Regards,
Indrajit