How can I test a number of columns in a data.table for a specific value using R

Question

As you can see, I am having a test variable and on that, I am having a table:

test <- data.table(name  = c("mike", "kate", "jeff"), ownership = c("1", "3", "4"), worth = c("1", "2", "3"), tax = c("4", "1", "4"))

I am trying to test if any rows (people) contain a row that contains "1".

I have tried the following but I want my syntax to be a bit more concise.

test <- test[ownership == "1" | worth == "1" | tax == "1", status := "yes"]

Answer 1

For getting the desired output in R programming, you can simply use rowSums() function :

cols <- c('ownership', 'worth', 'tax')

setDT(test)[rowSums(test[, ..cols] == 1) > 0, yes := 'yes']

test

#   name ownership worth tax  yes

#1: mike         1     1   4  yes

#2: kate         3     2   1  yes

#3: jeff         4     3   4 <NA>