Convert a presence/ absence matrix to a list of presence only
try this; added an extra row so that the lengths would not be even:
x <- read.table(textConnection(" spl_A spl_B spl_C
+ spcs1 1 1 0 + spcs2 1 0 1 + spcs3 0 1 1 + spcs4 0 0 1"), header = TRUE)
closeAllConnections() x
spl_A spl_B spl_C spcs1 1 1 0 spcs2 1 0 1 spcs3 0 1 1 spcs4 0 0 1
# get maximum in any column so we can pad out the lengths
maxLen <- max(colSums(x))
combine <- lapply(x, function(.col){
+ sp <- row.names(x)[.col == 1]
+ c(sp, rep("", maxLen - length(sp)))
+ })
do.call(cbind, combine)
spl_A spl_B spl_C [1,] "spcs1" "spcs1" "spcs2" [2,] "spcs2" "spcs3" "spcs3" [3,] "" "" "spcs4"
On Fri, Apr 22, 2011 at 2:10 PM, antu <ananta.acharya at gmail.com> wrote:
this thread (http://r.789695.n4.nabble.com/how-to-combine-presence-only-data-sets-to-one-presence-absence-table-td830140.html ) covered the need for making present list list to a matrix, Now, I ran into an opposite problem. I have a data matrix with 0, 1 on them, what I need now is list of presence only for each column name ie, this is what I have ? ? ? ?spl_A ? spl_B ? spl_C spcs1 ? 1 ? ? ? 1 ? ? ? 0 spcs2 ? 1 ? ? ? 0 ? ? ? 1 spcs3 ? 0 ? ? ? 1 ? ? ? 1 this is what I need spl_A ? ? spl_B spl_C spcs1 ?spcs1 ? ?spcs2 spcs2 ? ?spcs3 ?spcs3 Thank you -- View this message in context: http://r.789695.n4.nabble.com/Convert-a-presence-absence-matrix-to-a-list-of-presence-only-tp3468479p3468479.html Sent from the R help mailing list archive at Nabble.com.
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