From: Waverley <waverley.paloalto_at_gmail.com>

Date: Sun, 09 Mar 2008 16:22:30 -0700

Date: Sun, 09 Mar 2008 16:22:30 -0700

Hi,

I have a matrix

a = matrix (1:16, 4, 4)

b = c (2,3)

I want to find out which rows of a, where a[,1] equals any values of b?

I know that if b is only one value, e.g, b=2, then what I want is a[a[,1] == 2,]

But what about if it is not one value but a vector of values?

Thanks much in advance.

-- Waverley @ Palo Alto ______________________________________________ R-help_at_r-project.org mailing list 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.Received on Sun 09 Mar 2008 - 23:26:16 GMT

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