R Programming Using iteration value to change field names

Question

I am new to R programming, this is my test data frame :

 Day1.balc Day2.balc Day3.balc Day4.balc
x       100        20        30        40
y       100        10        10        10

> class(test)
[1] "data.frame"

I want to accomplish the following:

Day2.balc <- Day2.balc + Day1.balc
Day3.balc <- Day3.balc + Day2.balc
.
.
.
Day30.balc <- Day30.balc + Day29.balc

# Testing for first 4 days 
for (i in 1:4 ) {
   test$Day[i].balc <- test$Day[i].balc + test$Day[i-1].balc
}

I'm not sure if my code is right, any help would be appreciated.

Answer 1

Remove the first and last column from the test dataset and combine the datasets together:

Days <- test[-1] + test[-ncol(test)]