Quick R syntax question
If we assume that your data are in a data frame (which doesn't allow spaces in column names, hence the periods in the call below):
df = data.frame(Major.Gleason = c(4,5,2,3), Minor.Gleason = c(3,2,4,3))
You can paste together the contents of the two columns with a plus sign in between using the paste() function. The sep='' option at the end of the function call specifies that no spaces should be included between pasted items.
output = paste(as.character(df [,'Major.Gleason']), '+', as.character(df[ ,'Minor.Gleason']), sep='')
The new object 'output' is a character vector containing the 4 strings you're after:
print(output)
[1] "4+3" "5+2" "2+4" "3+3"
On Mon, Jun 20, 2011 at 11:31 AM, Ben Ganzfried <ben.ganzfried at gmail.com> wrote:
Hi --
I had a pretty quick R question since unfortunately I have not been able to
find an answer on Google. ?It shouldn't take much more than a minute to
answer.
I'm trying to add up the major gleason grade and minor gleason grade for an
analysis of patients with prostate cancer. ?One column has values under
"Major Gleason" and another column has values under "Minor Gleason." ?For
example,
Major Gleason ? ? Minor Gleason
4 ? ? ? ? ? ? ? ? ? ? ? ? 3
5 ? ? ? ? ? ? ? ? ? ? ? ? 2
2 ? ? ? ? ? ? ? ? ? ? ? ? 4
3 ? ? ? ? ? ? ? ? ? ? ? ? 3
I want my output to be:
"4+3"
"5+2"
"2+4"
"3+3"
The quasi-pseudocode in Java is basically:
major = column$majorGleason
minor = column$minorGleason
for item in len(Major Gleason) {
?string s = major(item) "+" minor(item);
}
return s;
But trying the same idea in R:
string <- major "+" minor
gives me an error: "unexpected string constant in..."
I would greatly appreciate any help.
Thanks,
Ben
? ? ? ?[[alternative HTML version deleted]]
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