multiply all values in all columns by the number of days that correspond to the month in date?-CodePudding

An example of my data is here

    dput(s2[2,])
 structure(list(date = structure(4049, class = "Date"), `A` = 7, 
`At` = 0.0001780556), row.names = 2L, class = "data.frame")

How can I multiply all values in all columns by the number of days that correspond to the month in date and multiply by 10

CodePudding user response：

With days_in_month function from lubridate we could extract the days of the present month, in this case 28 and then use across for each column except date and multiple by days_in_month(date) and by 10:

library(lubridate)
library(dplyr)
df %>% 
  mutate(across(-date, ~days_in_month(date)*.*10))

        date    A         At
2 1981-02-01 1960 0.04985557

In case you want to keep the original values:

df %>% 
  mutate(across(-date, ~days_in_month(date)*.*10, .names = "calculated_{.col}"))

        date A           At calculated_A calculated_At
2 1981-02-01 7 0.0001780556         1960    0.04985557

Or as suggested by @mkpt_uk:

df %>% 
  mutate(across(-date, list(mult = ~days_in_month(date)*.*10)))

        date A           At A_mult    At_mult
2 1981-02-01 7 0.0001780556   1960 0.04985557