From: Dimitris Rizopoulos <dimitris.rizopoulos_at_med.kuleuven.be>

Date: Wed 27 Jul 2005 - 19:13:26 EST

Dimitris Rizopoulos

Ph.D. Student

Biostatistical Centre

School of Public Health

Catholic University of Leuven

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

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Wed Jul 27 19:12:27 2005

Date: Wed 27 Jul 2005 - 19:13:26 EST

look at ?sum() and use the `na.rm' argument, i.e.,

sum((x - y)^2 / x, na.rm = TRUE)

I hope it helps.

Best,

Dimitris

p.s., R is vectorized, you don't have to use `x[i]' in your example.

Dimitris Rizopoulos

Ph.D. Student

Biostatistical Centre

School of Public Health

Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium

Tel: +32/16/336899 Fax: +32/16/337015 Web: http://www.med.kuleuven.be/biostat/ http://www.student.kuleuven.be/~m0390867/dimitris.htm

- Original Message ----- From: "Chun-Ying Lee" <u9370004@cc.kmu.edu.tw> To: <r-help@stat.math.ethz.ch> Sent: Wednesday, July 27, 2005 10:51 AM Subject: [R] how to overlook the zero in the denominator

> Dear R users:

*>
**> I have two set of data, as follow:
**> x<-c(0,0,0.28,0.55,1.2,2,1.95,1.85,
**> 1.6,0.86,0.78,0.6,0.21,0.18)
**> y<-c(0,0,0,0.53,1.34,1.79,2.07,1.88,
**> 1.52,0.92,0.71,0.55,0.32,0.19)
**> i<-1:length(x)
**>
**> I want to sum each (x[i]-y[i])^2/x[i] together,
**> like:
**>>Sum <-sum((x[i]-y[i])^2/x[i])
**>>Sum
**> [1] NaN
**>
**> Because the denominator shoud not be zero.
**> So I want to overlook those when x[i]=0,
**> and just to sum those x[i] not equal to 0.
**> What should I do?
**> Any suggestion.
**> Thanks in advance !!
**>
**>
*

*> ______________________________________________
**> R-help@stat.math.ethz.ch mailing list
**> https://stat.ethz.ch/mailman/listinfo/r-help
**> PLEASE do read the posting guide!
**> http://www.R-project.org/posting-guide.html
*

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

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Wed Jul 27 19:12:27 2005

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