I am trying to exponent a certain part of the data set here.

I have a table like this: Called DF

I only want to apply an operation on the second row, starting on George, and just the section between XPL, WAYS and SPM. I do not want to do any calculation on the first row.

The end result, I want to put that number to the power of 3, so for example, 3^23 for George at XPL. What is the best way to do this for a large data set where it would be hard to "hard code" it?

So ideally, I would have the numerical value for the section applied. Any suggestions would be appreciated!

Participant <- c("Location", "George", "Sam", "Carl")
Date <- c("TBD", "10_Sep_Mon", "10_Sep_Mon", "10_Sep_Mon")
XPL <- c(12, 23, 14, 21)
WAYS <- c(3, 12, 2.5, 2.8)
SPM <- c(5.5, 12.7, 5, 5.1)
DF <- data.frame(Participant, Date, XPL, WAYS, SPM)

CodePudding user response：

Using dplyr:

library(dplyr) 

DF %>% mutate(across(XPL:SPM, ~ c(.x[1], 3^.x[-1])))
#>   Participant       Date         XPL         WAYS          SPM
#> 1    Location        TBD          12      3.00000       5.5000
#> 2      George 10_Sep_Mon 94143178827 531441.00000 1146673.9198
#> 3         Sam 10_Sep_Mon     4782969     15.58846     243.0000
#> 4        Carl 10_Sep_Mon 10460353203     21.67402     271.2179

^{Created on 2022-09-28 with reprex v2.0.2}

CodePudding user response：

Using base R

DF[-1, 3:5] <- 3^DF[-1, 3:5]

-output

> DF
  Participant       Date         XPL         WAYS          SPM
1    Location        TBD          12      3.00000       5.5000
2      George 10_Sep_Mon 94143178827 531441.00000 1146673.9198
3         Sam 10_Sep_Mon     4782969     15.58846     243.0000
4        Carl 10_Sep_Mon 10460353203     21.67402     271.2179