From: Berton Gunter <gunter.berton_at_gene.com>

Date: Tue 20 Jul 2004 - 04:32:25 EST

R-help@stat.math.ethz.ch mailing list

https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Tue Jul 20 04:46:25 2004

Date: Tue 20 Jul 2004 - 04:32:25 EST

How about:

X<-as.matrix(yourframe)

apply(X,2, '==',X[,1])%*%rep(1,ncol(X)) == ncol(x)

avoiding the rowwise apply overhead?

Cheers,

Bert Gunter

Non-Clinical Biostatistics

Genentech

MS: 240B

Phone: 650-467-7374

"The business of the statistician is to catalyze the scientific learning process."

- George E.P. Box F Duan wrote:

> Dear All,

*>
**>
**>
**> I have a data frame with n columns: X1, X2, ., Xn. Now I want to create a
**> new column: if X1 = X2 = . = Xn, the value is 1; Otherwise, the value is 0.
**>
**>
**>
**> How to do that in a quick way instead of doing (n choose 2) comparisons?
**>
**>
**>
**> Thank you,
**>
**>
**>
**> Frank
**>
**> [[alternative HTML version deleted]]
**>
**> ______________________________________________
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R-help@stat.math.ethz.ch mailing list

https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Tue Jul 20 04:46:25 2004

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