M <- matrix(c(2,2,rep(1,12), 2), nrow = 5,byrow = FALSE) ix <- expand.grid( r = seq.int( nrow( M ) ) , c = seq.int( ncol( M ) ) ) ix[ 1 == c(M), ]
On June 10, 2020 5:29:10 PM PDT, Jinsong Zhao <jsz...@yeah.net> wrote: >Hi there, > >I have a matrix similar as: > >M <- matrix(c(2,2,rep(1,12), 2), nrow = 5,byrow = FALSE) > >I hope to get the border subscript of the block with value 1. In the >above example, I hope to get: > >(3,1), (5,1), (5,2), (4,2), (4,3), (1,3), (1,2), (3,2) > >Is there any function can do that? or any implement idea? Thanks! > >Best, >Jinsong > >______________________________________________ >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >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. -- Sent from my phone. Please excuse my brevity. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.