Dear Contributors, I am asking help on the way how to solve a problem related to loops for that I always get confused with. I would like to perform the following procedure in a compact way.
Consider that p is a matrix composed of 100 rows and three columns. I need to calculate the sum over some rows of each column separately, as follows: fa1<-(colSums(p[1:25,])) fa2<-(colSums(p[26:50,])) fa3<-(colSums(p[51:75,])) fa4<-(colSums(p[76:100,])) fa5<-(colSums(p[1:100,])) and then I need to apply to each of them the following: fa1b<-c() for (i in 1:3){ fa1b[i]<-(100-(100*abs(fa1[i]/sum(fa1[i])-(1/3)))) } fa2b<-c() for (i in 1:3){ fa2b[i]<-(100-(100*abs(fa2[i]/sum(fa2[i])-(1/3)))) } and so on. Is there a more efficient way to do this? Thanks for your time! Francesca ---------------------------------- Francesca Pancotto, PhD Università di Modena e Reggio Emilia Viale A. Allegri, 9 40121 Reggio Emilia Office: +39 0522 523264 Web: https://sites.google.com/site/francescapancotto/ ---------------------------------- [[alternative HTML version deleted]]
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