useR's, This is a follow up question to one I previously asked. Consider the 3-element list below
> res [[1]] [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13] [,14] [1,] NA NA NA 1.25 0.25 0.75 NA NA NA NA NA NA 1.25 0.25 [2,] 1.25 0.25 0.75 NA NA NA NA NA NA 1.25 0.25 0.75 NA NA [3,] NA NA NA NA NA NA 1.25 0.25 0.75 NA NA NA NA NA [4,] NA NA 1.25 0.25 0.75 NA NA NA NA NA NA 1.25 0.25 0.75 [5,] NA NA NA NA NA 1.25 0.25 0.75 NA NA NA NA NA NA [[2]] [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13] [,14] [1,] NA NA NA NA NA NA NA NA NA NA NA NA NA 1.25 [2,] 1.25 NA NA NA NA NA NA NA NA NA NA NA NA NA [3,] 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25 0.25 0.25 0.25 0.25 0.25 [4,] NA NA NA NA NA NA NA NA NA NA NA NA NA NA [5,] NA NA NA NA NA 1.25 NA NA NA NA NA NA NA NA [[3]] [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13] [,14] [1,] NA NA NA NA NA NA NA NA NA NA NA NA NA 1.25 [2,] 0.25 NA NA NA NA NA NA NA NA NA NA NA NA NA [3,] 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25 0.25 0.25 0.25 0.25 0.25 [4,] NA NA NA NA NA NA NA NA NA NA NA NA NA NA [5,] NA NA NA NA NA 0.25 NA NA NA NA NA NA NA NA What I want to do is find the values that are not NA simultaneously for each value in each element of the list, and then average these numbers and store them in a 14x1 vector. For example, in position (2,1) in each of the 3 elements of the res list, there is a value, 1.25 in [[1]] and [[2]], 0.25 in [[3]]. Since there is a value in this position in all elements of the list I want to average these numbers: (1.25+1.25+0.25)/3 and store this value in a numeric vector. So, if there are not 3 values to average, this means that a given position (i,j) does not have a value in each element of the list and thus I want to store NA in the 14x1 vector. In the end, the 14x1 vector will be mixed with values and NA's or NaN's. Does anyone know a efficient way to do this? Maybe using mapply()? I hope it is clear. Thank you for any input. Derek -- View this message in context: http://www.nabble.com/using-mapply%28%29-tp14697351p14697351.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.