r - How to perform element-wise statistics over numerous (distance) matrices -
i have several thousand distance matrices (converted matrix using as.dist()) , compute mean, sd, median etc each matrix element.
to illustrate:
matrix.a
1 7 1 5 2 1   matrix.b
2   3 4 1 1 3   etc...
for example, if have sum of individual elements do:
sum.matrix <- matrix.a + matrix.b   sum.matrix
3 10 5 6 3 4   but if have thousands of these matrices? , how can compute not sum each element means, sd etc? matrices stored in single list.
try
lst2 <- lapply(lst1, as.matrix) dim1 <- sapply(lst2, dim)[,1] l <- length(lst1) ar1 <- array(unlist(lst2), dim=c(dim1, l))   as.dist(apply(ar1, 1:2, sum)) as.dist(apply(ar1, 1:2, mean)) as.dist(apply(ar1, 1:2, sd))   data
set.seed(24) lst1 <- lapply(1:4, function(i) dist(sample(1:10,4, replace=true)))      
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