[R] Carrying a value down a data.frame conditionally

[Pooya Lalehzari]

Hello,
I have a data.frame (below) containing the two fields of "Value" and "Signal" and I would need to create the third field of "To_Be_Produced". The condition for producing the third field is to carry the 1 in the "Signal" field down until "Value" is below 40.
Do I have to create a for-loop to do this or will I be able to do anything else more efficient?


df <- data.frame( Value=c(0,0,100,85,39,1,30,40,20,20,0,0),
                  Signal=c(0,1,0,0,0,0,0,0,0,1,0,0),
                  To_Be_Produced= c(0,1,1,1,0,0,0,0,0,1,0,0)
                )

Thank you,
Pooya.




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