I am looking for a convenient way to convert positive values (proportions) into negative values of the same variable, depending on the value of another variable.
This is how the data structure looks like:
id Item Var1 Freq
1 P1 0 0.043
2 P2 1 0.078
3 P3 2 0.454
4 P4 3 0.543
5 T1 0 0.001
6 T2 1 0
7 T3 2 0.045
8 T4 3 0.321
9 A1 0 0.671
...
More precisely, I would like to put the numbers for Freq into the negative if Var1 <= 1 (e.g. -0.043).
This is what I tried:
for(i in 1: 180) {
if (mydata$Var1 <= "1") (mydata$Freq*(-1))}
OR
mydata$Freq[mydata$Var1 <= "1"] = -abs(mydata$Freq)}
In both cases, the negative sign is rightly set but the numbers are altered as well.
Any help is highly appreciated. THANKS!
new.Freq <- with(mydata, ifelse(Var1 <= 1, -Freq, Freq))