R: How to make a for loop that performs a formula over a few columns (variables) in a new variable

Question

Is it possible to make a for loop in a data frame that produces an outcome value for every row stored in a new variable/column (i.e., 3 columns (variables) X, Y, and Z. that produces value A for every row depending on values of the same row in those variables).

For example I want to do 0.5X * 1.2Y + 0.75Z and put the value in a new column and then loop the same formula for all the rows

Thanks in advance!

Answer 1

A dplyr option:

library(dplyr)
df %>%
  mutate(new = 0.5*X*1.2*Y+0.75*Z)

Output:

  X Y Z  new
1 1 3 5 5.55
2 4 2 2 6.30
3 2 5 1 6.75

Data

df <- data.frame(X = c(1,4,2),
                 Y = c(3,2,5),
                 Z = c(5,2,1))