Note: I'm a beginner but I'm trying to switch from excel to R doing some backtesting for a trading strategy. I'm having a data.frame with vectors of prices, indicator signal (Buy/Sell), etc.
What I need to do is to have a new sequential vector or "column" (actually a number of them), which is always going to (as part of a nested ifelse) also look at the previous row to determine the correct response and/or it's going to copy the value from its previous row if a condition is met.
One of the nested ifelse should work more or less in this fashion (sorry for the excel-type logic):
my_data$Status <- ifelse(the value in previous row is any of three values (0,"Buy","Sell), my_data$MTM,
ifelse(my_data$MTM== 0, 0,
ifelse(my_data$MTM<= variable1, "TP",
I can actually get it done through the "for loop" mechanism but it doesn't help my speed issues which I'm having with excel (actually this takes more time now with R)...
I'm receiving various errors, probably because the first row in such a function is referencing to the header, or that the new vector is being built using "itself" so it cannot even be started and throws a logical error...
Thanks a million for any help!