Conditional Logic and Looping - r

Question

I am trying to create a conditional loop to create a new variable called BigSales which should be given a value of 'yes' if either the date occurred before 2012 or the total gross for the day exceeded $65 million. Otherwise, it should be given a value of 'no'.
I tried:
for(i in 1:45){
if(movies$Gross[i] > 65 | movies$Date[i] < 2012-01-01){
movies$BigSales[i] <- "yes"}
else (
movies$BigSales[i] <- "no"
)
}
But I got the error message:
Error in if (movies$Gross[i] > 65 | movies$Date[i] < 2012 - 1 - 1) { :
missing value where TRUE/FALSE needed
In addition to that, the data set contains 100 observations, but it is only reading 45. How can I solve this?

Answer 1

It's possible to add a conditional column in this matter, but there are tools out there that make this easier and more comprehensible.
library(plyr)
library(dplyr)
movies <- mutate(movies, BigSales = ifelse(Gross > 65 && Date < "2012-01-01","yes","no"))
You should also be careful working with dates - call str(movies$Date) to make sure it's of the "Date" type, and if not you should pass it to as.Date
To answer your question as you asked it, you didn't put quotes around the date you listed, so it tried to evaluate it as 2012 - 2. If you'd prefer to solve this problem with the code you have, use "2012-01-01"

Answer 2

ifelse is vectorised, meaning it takes each item from input vector, process for the condition and returns a vector.
Another point is that since OP has mentioned that date before 2012 will be considered as BigSales "yes". Hence checking for only year of movies$Date will do the trick.
In base R, solution could be in
movies$BigSales <- ifelse(movies$Gross > 65 | as.numeric(format(movies$Date,"%Y")) < 2012,
"yes", "no")
Note : movies$Date is expected of type Date or POSIXct