Hi r-help-boun...@r-project.org napsal dne 08.06.2010 11:46:17:
> Hi, > > You are using if/then/else which is a logical control statement and so doesn't > return a value, see > ?if > for details. > > You are probably looking for the ifelse function. Or use possibility of easy conversion logical (T/F) to numeric (1/0) rr.dia.2m - (med.hyper==1)*5 Regards Petr > > Martyn > > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf Of Peter Lercher > Sent: 08 June 2010 10:18 > To: r-help@r-project.org > Subject: [R] problem with if else statement > > Dear colleagues, > > What did I not understand ? > > ->my intention > I want to create a new variable: > In plain language: > If someone is taking anithypertensive treatment (med.hyper==1) > table(med.hyper) > med.hyper > 0 1 > 472 97 > I want to subtract 5 mmHg (rr.dia.2m-5) from the measured diastolic blood > pressure (rr.dia.2m) if not treated - the value of the measured diastolic > blood pressure should remain the same > > ->my code (data frame is attached !) > rr.dia2.corr<-if(med.hyper==1) > { > rr.dia.2m-5 > } else > { > rr.dia2.corr==rr.dia.2m > } > > R warning > Warnmeldung: > In if (med.hyper == 1) { : > Bedingung hat Länge > 1 und nur das erste Element wird benutzt "Only first > condition is use" > which you can see from the result (simply 5 mm was subtracted and the second > condition was taken into account) > > > describe(rr.dia.2m) > rr.dia.2m > n missing unique Mean .05 .10 .25 .50 > .75 .90 .95 > 546 26 110 85.32 67.00 71.50 77.62 84.50 > 92.00 99.25 105.00 > > lowest : 45.0 57.0 60.0 61.0 62.0, highest: 127.5 128.5 129.5 142.5 > 146.5 > > describe(rr.dia2.corr) > rr.dia2.corr > n missing unique Mean .05 .10 .25 .50 > .75 .90 .95 > 546 26 110 80.32 62.00 66.50 72.62 79.50 > 87.00 94.25 100.00 > > lowest : 40.0 52.0 55.0 56.0 57.0, highest: 122.5 123.5 124.5 137.5 > 141.5 > -------------------- > OS windows > R version 2.10.1 (2009-12-14) > attached R modules: design+hmisc > ------------------ > Thank you so much > > Peter > > > > ________________________________________________________________________ > This e-mail has been scanned for all viruses by Star.\ _...{{dropped:12}} > > ______________________________________________ > R-help@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. ______________________________________________ R-help@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.