mean average precision in R -

how can calculte mean average precision score in r ? there easy way?

i calculate follows. dont know if totally true or not..

pr = prediction(preds, labs) pf = performance(pr, "prec", "rec") # plot(pf)  pf@x.name  [1] "recall"  pf@y.name  [1] "precision"  rec = pf@x.values[[1]]  prec = pf@y.values[[1]]  idxall = null for(i in 1:10){   = i/10    # find closest values in recall values 0, 0.1, 0.2, ... ,1.0   idx = which(abs(rec-i)==min(abs(rec-i)))    # there more 1 value return, choose value in middle   idx = idx[ceiling(length(idx)/2)]     idxall = c(idxall, idx) }  prec.mean = mean(prec[indx]) 

here's example metrics package.