[R] adding column of ordered numbers to matrix

[Greg Snow]

> newmat <- cbind( oldmat, order=seq(nrow(oldmat)) )

See ?seq and/or ?rev for descending.

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Assa Yeroslaviz
> Sent: Thursday, June 10, 2010 7:56 AM
> To: r-help at stat.math.ethz.ch
> Subject: [R] adding column of ordered numbers to matrix
> 
> Hello everyone,
> 
> I have a matrix of over 40000 line and about 30 columns.
> 
> For my analysis I would like to add another column with ascending
> numbers
> (column header should be "order", and than 1,2,3,4 ....the end of the
> matrix).
> During my analysis I reorder them ( due to merge commands by a
> different
> column).
> 
> How do I add such a column in an ascending order (or descending for
> what it
> matters)?
> 
> THX
> 
> Assa
> 
> 	[[alternative HTML version deleted]]
> 
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