10. > small.ints = to.dfs(1:10) > out = mapreduce(input = small.ints, map = function(k,v) keyval(k, k^2)) > res = from.dfs(out) > colres <- do.call('rbind', lapply(res,"[[",2)) > t(colres) [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [1,] 1 4 9 16 25 36 49 64 81 100 > groups = to.dfs(rbinom(32, n = 50, prob = 0.4)) > out = mapreduce(input = groups, reduce = function(k,vv) keyval(k, length(vv
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