6 messages · kayj, Sarah Goslee, Seeliger.Curt at epamail.epa.gov +3 more
I have a problem with ifelse(), I do not understand how it works.
X<-c(2,2,1,1,0,0) str(X)
num [1:6] 2 2 1 1 0 0
Y<-ifelse(X>0,1,0) Y
[1] 1 1 1 1 0 0
Can some one explain what is going on, I do not understand what ifelse is doing in this case. Can someone explain the output Y. Thanks
View this message in context: http://www.nabble.com/ifelse%28%29-tp21943308p21943308.html Sent from the R help mailing list archive at Nabble.com.
Did you read the helpfile? If your condition is true, the first option is returned. If it is false, the second option is returned. For the first four elements of X, all of which are greater than zero, 1 is returned. For the last two, which are not greater than zero, 0 is returned. Sarah
I have a problem with ifelse(), I do not understand how it works.
X<-c(2,2,1,1,0,0) str(X)
num [1:6] 2 2 1 1 0 0
Y<-ifelse(X>0,1,0) Y
[1] 1 1 1 1 0 0
Can some one explain what is going on, I do not understand what ifelse is doing in this case. Can someone explain the output Y. Thanks
Sarah Goslee http://www.functionaldiversity.org
An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20090210/dd84803e/attachment-0001.pl>
-----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of kayj Sent: Tuesday, February 10, 2009 1:44 PM To: r-help at r-project.org Subject: [R] ifelse() I have a problem with ifelse(), I do not understand how it works.
X<-c(2,2,1,1,0,0) str(X)
num [1:6] 2 2 1 1 0 0
Y<-ifelse(X>0,1,0) Y
[1] 1 1 1 1 0 0
Can some one explain what is going on, I do not understand what ifelse is doing in this case. Can someone explain the output Y. Thanks
ifelse goes through your vector X, 1 element at a time, and if the element is greater than zero it returns a 1, otherwise, 0. The resulting vector of 1s and 0s is assigned to Y Hope this is helpful, Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204
Take it in a couple of steps. 'ifelse' will take the evaluation of a logical vector (first parameter) and return it second parameter if TRUE or the third parameter if FALSE:
X<-c(2,2,1,1,0,0) X > 0
[1] TRUE TRUE TRUE TRUE FALSE FALSE
ifelse(X > 0, 1,0)
[1] 1 1 1 1 0 0
Now the second and third parameters can also be vectors and the corresponding value will be chosen:
ifelse(X > 0, 1:6, 11:16)
[1] 1 2 3 4 15 16
HTH
I have a problem with ifelse(), I do not understand how it works.
X<-c(2,2,1,1,0,0) str(X)
num [1:6] 2 2 1 1 0 0
Y<-ifelse(X>0,1,0) Y
[1] 1 1 1 1 0 0
Can some one explain what is going on, I do not understand what ifelse is doing in this case. Can someone explain the output Y. Thanks -- View this message in context: http://www.nabble.com/ifelse%28%29-tp21943308p21943308.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ 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.
Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
An embedded and charset-unspecified text was scrubbed... Name: not available URL: <https://stat.ethz.ch/pipermail/r-help/attachments/20090210/5bd626ca/attachment-0001.pl>