Suppose I have a dataframe that has multiple components and their properties listed out in multiple columns and I want to run multiple functions against the columns. My approach was to try and base it off the substring in each column header, but I haven't been able to figure out how to do that. Below is an example of the data frame.
Basket F_Type_1 F_Qty_1 F_P_1 F_Type_2 F_Qty_2 F_P_2
AAA Apple 10 2.5 Banana 9 2
BBB Peach 5 6 Melon 20 5
I essentially want to cbind two new columns to the end of this dataframe that multiplies Qty and P so you get two new columns at the end like below.
F_Total_1 F_Total_2
25 18
30 100
The input is dynamic so on occasion it could be 2 fruits or 10 fruits in certain baskets. But I can figure that portion out, it's moreso trying to figure out how to multiply columns based on the Substrings '1' or '2'.
I appreciate all your help and any other approaches you may have!
We create a function that finds the specific names, and then calculates the rowwise products. The heavy lifter of this function is the mapply function. We add a final step to rename the resultant data.frame.
fun1 <- function(data){
qty_names <- names(data)[grepl(pattern = "Qty", x = names(data))]
p_names <- names(data)[grepl(pattern = "P", x = names(data))]
setNames(
data.frame(
mapply(qty_names, p_names,
FUN = function(n1, n2) apply(data[c(n1,n2)], 1, prod))),
paste0('F_Total_', 1:length(p_names)))
}
cbind(dat, fun1(dat))
Basket F_Type_1 F_Qty_1 F_P_1 F_Type_2 F_Qty_2 F_P_2 F_Total_1 F_Total_2
1 AAA Apple 10 2.5 Banana 9 2 25 18
2 BBB Peach 5 6.0 Melon 20 5 30 100