Dear Rheannon,

Try

DF = c(4, 3, 2, 1, 0, -1, -2, -3, -2, 2, 1, -1, -2, -3, -2, -1, 1, 2)
sum(DF[DF<0])
[1] -17

HTH,

Jorge



On Tue, Jul 15, 2008 at 5:35 PM, Rheannon <rbrooks@uvic.ca> wrote:

>
> Hello,
>
> I'd like to sum the values of a row from the first negative number (FN) to
> the last negative number (LN), but not add any positive values to the sum.
> Then apply this to each row of the data frame.
>
> For example if I have a dataframe with Row 1 values
> DF = (4, 3, 2, 1, 0, -1, -2, -3, -2, 2, 1, -1, -2, -3, -2, -1, 1, 2)
> I would like to sum the numbers from column 6 to column 16, but not include
> column 10 & 11.
>
> I believe it would look something like
>
> function(x)while x[FN + 1] != 0 && x[FN] != LN sum(x[FN] to x[FN + 1]); FN
> =
> FN + 1
>
> But I cant seem to get the sintax right.
> Could someone help me?
> Cheers,
> R
>
> --
> View this message in context:
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> Sent from the R help mailing list archive at Nabble.com.
>
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