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[Rcpp-devel] Negative indexing in Rcpp

2 messages · Tiago Fragoso, Dirk Eddelbuettel

Original
Tiago Fragoso
# 
Hello,

Say I have a 10x10 matrix A. If I want to access everything remaining after
I delete columns 1, 5 and 10, all I have to do is

A[,-c(1,5,10)]

Is there a convenient way to do it in Rcpp (or using Armadillo objects)?

Best regards,

Tiago
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Dirk Eddelbuettel
# 
Hi Tiago,
On 1 April 2013 at 17:41, Tiago Fragoso wrote:
| Say I have a 10x10 matrix A. If I want to access everything remaining after I
| delete columns 1, 5 and 10, all I have to do is?
| 
| A[,-c(1,5,10)]
| 
| Is there a convenient way to do it in Rcpp (or using Armadillo objects)?

Armadillo allows you to subset via vector expressions.

Dirk