Odp: Counting rows given conditional
Hi r-help-bounces at r-project.org napsal dne 04.08.2011 14:56:09:
a217 <ajn21 at case.edu> Odeslal: r-help-bounces at r-project.org 04.08.2011 14:56 Komu r-help at r-project.org Kopie P?edm?t [R] Counting rows given conditional Hello, I have an input file that contains multiple columns, but the column I'm concerned about looks like: "TR" 5 0 4 1 0 2 0 To count all of the rows in the column I know how to do NROW(x$TR) which gives 7. However, I would also like to count only the number of rows with values =1 (i.e. not 0). I've tried NROW(x$TR>=1) which did not give the intended output.
You are quite close. x$TR>=1 gives you logical vector TRUE/FALSE. You can compute count of TRUE values by sum(logical.vector) e.g. sum(x$TR>=1) Regards Petr
Do any of you have any suggestions as to where I'm going wrong? -- View this message in context:
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