conditional statements - conditionally multiply a vector by another r -

i have next vector

trans<- c(-2,3,10,-5,-2,56,0)

and want multiply each element selection of 2 vectors depending on whether initial number positive or negative

negtrans<-c(1,2,3) postrans<-c(4,5,6,7)

the result should -2 12 50 -10 -6 336 0

the key here maintain order intact

one way is

unsplit(map(`*`, split(trans, trans>=0),                 list(negtrans, postrans)),trans>=0) #[1]  -2  12  50 -10  -6 336   0

r conditional-statements

Jaimee