Calculating percentages of each colomn in R-CodePudding

I have a wide data frame, where one column has a variable name and the other columns have measurements. For each cell in a column I would like to paste in the percentage value that cell contributes to the whole coloumn. So for example, I would like to take this:

Ship    Month1    Month2    Month3    Month4
A         5         10        5          10
B         7         30        5          0
C         3         5         5          0
D         5         5         5          0

And have in it's place something like this:

Ship    Month1            Month2       Month3           Month4
A         5 (25%)         10 (20%)       5 (25%)         10 (100%)
B         7 (35%)         30 (60%)       5 (25%)         0  (0%)
C         3 (15%)         5  (10%)       5 (25%)         0  (0%)
D         5 (25%)         5  (10%)       5 (25%)         0  (0%)

How would I be able to go around doing that?

CodePudding user response：

Base R:

cols = grep('Month', names(df))
df[cols] <- lapply(df[cols], \(x) sprintf("%d (%s%%)", x, x / sum(x) * 100))

#   Ship  Month1   Month2  Month3    Month4
# 1    A 5 (25%) 10 (20%) 5 (25%) 10 (100%)
# 2    B 7 (35%) 30 (60%) 5 (25%)    0 (0%)
# 3    C 3 (15%)  5 (10%) 5 (25%)    0 (0%)
# 4    D 5 (25%)  5 (10%) 5 (25%)    0 (0%)

Made more concise with magrittr:

library(magrittr)
df[cols] %<>% lapply(\(x) sprintf("%d (%s%%)", x, x / sum(x) * 100))

Reproducible data:

df = data.frame(
  Ship   = c("A", "B", "C", "D"), 
  Month1 = c( 5L,  7L, 3L, 5L), 
  Month2 = c(10L, 30L, 5L, 5L), 
  Month3 = c( 5L,  5L, 5L, 5L), 
  Month4 = c(10L,  0L, 0L, 0L)
)