Help with data iteration

tidyverse
2

This example does not use your data. See the FAQ: How to do a minimal reproducible example reprex for beginners.

suppressPackageStartupMessages({
  library(dplyr)
})

dat <- data.frame(
  A =
    c(10, 20, 50, 30, 15),
  B =
    c(5, 5, 20, 60, 50),
  C =
    c(5, 5, 25, 35, 70),
  D =
    c(10, 20, 50, 30, 15),
  E =
    c(5, 20, 60, 50, 40),
  F =
    c(25, 35, 70, 50, 30))

dat %>% rowwise() %>% mutate(Max = max(c(A,B,C,D,E,F)))
#> # A tibble: 5 x 7
#> # Rowwise: 
#>       A     B     C     D     E     F   Max
#>   <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1    10     5     5    10     5    25    25
#> 2    20     5     5    20    20    35    35
#> 3    50    20    25    50    60    70    70
#> 4    30    60    35    30    50    50    60
#> 5    15    50    70    15    40    30    70