Windows 7
R 2.12.1
I am trying to write a function (see sample code below) that will take the 
output of a t-test and produce results suitable for a table.
I have two questions
(1) You will note that the name of the outcome variable, which is "value" in 
the input is replaced by the string "outcome by class" in the data frame 
produced by my function. How can I make my function put the name of the 
variable being analyzed,, i.e "value" in the output data frame
(2) How can I pass the entire input data to the function so my call to the 
function will not have to be in its current ugly form, i.e.  
Table1(data$value,data$sex)
and instead could just be
Table1(value,sex,data=data)
 
 
x <- data.frame(value=rnorm(20)  ,sex=rep("Male",  20))
y <- data.frame(value=rnorm(20,4),sex=rep("Female",20))
data <- rbind(x,y)
temp <- t.test(value~sex,data=data)
temp
v<-data.frame(dep=temp$data.name,
           female=temp$estimate[1],male=temp$estimate[2],
           p=temp$p.value,
           CILow=temp$conf.int[1],CIHigh=temp$conf.int[2])
row.names(v) <- NULL
 
 
 
Table1 <- function(outcome,class) {
temp <- t.test(outcome~ class)
mydf <- data.frame(dep=temp$data.name,
             female=temp$estimate[1],male=temp$estimate[2],
             p=temp$p.value,
             CILow=temp$conf.int[1],CIHigh=temp$conf.int[2])
row.names(mydf) <- NULL
mydf}
Table1(data$value,data$sex)
 
 
 
Thank you,
John
 
 
 
John David Sorkin M.D., Ph.D.
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524
(Phone) 410-605-7119
(Fax) 410-605-7913 (Please call phone number above prior to faxing)
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