[R] Create variable with AND IF statement

[ONKELINX, Thierry]

Dear Richard,

You can do this with some nested ifelse statements.
Assuming variable2.num has only positive integers and variable1.fac is only 0 or 1

Variable3 <- ifelse(variable1.fac == 0, ifelse(variable2.num == 0, 1, 2), ifelse(variable2.num == 0; 3; 4))

A more fancy solution

as.numeric(factor(variable1.fac):factor(ifelse(variable2.num == 0, 0, 1)))

Best regards,

Thierry

ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht
Belgium
Thierry.Onkelinx op inbo.be
www.inbo.be

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-----Oorspronkelijk bericht-----
Van: r-help-bounces op r-project.org [mailto:r-help-bounces op r-project.org] Namens Richard Kolodziej
Verzonden: maandag 2 januari 2012 10:11
Aan: r-help op r-project.org
Onderwerp: [R] Create variable with AND IF statement

Hello,

I'm using SPSS at work but really would like to switch to R. Right now I'm trying to learn R in reproducing calculations I did with SPSS but am stuck with something that is quite simple and comprehensible in SPSS-Syntax:

IF (variable1.fac = 0 AND variable2.num = 0) variable3=1.
IF (variable1.fac = 0 AND variable2.num >= 1) variable3=2.
IF (variable1.fac = 1 AND variable2.num = 0) variable3=3.
IF (variable1.fac = 1 AND variable2.num >= 1) variable3=4.

I want to create four different groups out of different conditions of two
variables:
  * variable1.fac is a factor coded with 0 and 1
  * variable2.num is a numerical variable with only whole numbers

My problem with R is that I can't find a way to use AND in an IF statement that doesn't produce an error or not intended solutions.

"An Introduction to R" is really unhelpful with this problem and I wouldn't have written here, if I didn't have searched for the answer.

http://tolstoy.newcastle.edu.au/R/help/05/09/12136.html was helpful in understanding how the IF statement is written in R but didn't answer my question how to add an usable AND (&, |) https://stat.ethz.ch/pipermail/r-help/2008-November/178808.html looked promising but didn't do what I had intended

Thanks in advance,
Richard

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