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[S] Yet Another Vectorization Question

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Subject: [S] Yet Another Vectorization Question
From: Kim Elmore <elmore@nssl.noaa.gov>
Date: Thu, 23 Sep 1999 13:38:49 -0500 (CDT)
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        I have a very simple operation that I'd like to vectorize.
However, I haven't figured out how to do it.  Being an unrepentant Fortran
77 hacker, this vectorization stuff sometimes escapes me.  Here's what I'm
after:  within a data frame, I want to know what columns contain negative
values and I want the results returned as a logical vector.

        This works, but uses looping:

test <- logical(0)
for (i in 1:100)
{
        test[i] <- all(df[,i] < 0)
}

        Surely there's a way to vectorize this.  Please, somebody rescue
me from my ignorance!

                Kim Elmore, [N5OP, PP ASMEL/Glider 2232456]
"All of Meteorology is divided into three parts: Yes, No and Maybe.  The
greatest of these is Maybe." -- The original Latin appears to be garbled.

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