Re: st: Integer values in Stata

[Nick Cox <njcoxstata@gmail.com>]

-int(end)- is not a true or false test of whether its argument is
integer. Rather it rounds towards zero, and the result is an integer:
if that result is non-zero if it is treated as true. That explains why
you got what you did.

keep if end == int(end)

is one way of selecting integers as values that are already integers
are unchanged by the function.

A similar example is already included in my talk for the London users'
meeting on functions.

Nick

On Thu, Sep 1, 2011 at 11:02 AM, Tim Evans <Tim.Evans@wmciu.nhs.uk> wrote:

> I have a list of values in a column in Stata like so:
>
> end
> .2
> .4
> .6
> .8
> 1
> 1.2
> 1.4
> 1.6
> 1.8
> 2
> 2.2
> 2.4
> 2.6
> 2.8
> 3
> 3.2
> 3.4
> 3.6
> 3.8
> 4
> 4.2
> 4.4
> 4.6
> 4.8
> 5
>
> and I wish to only keep the whole number value i.e. 1,2,3,4,5 etc. and drop any non integer values. I there use the following code
>
> keep if int(end)
>
> however, I still end up with the following values
>
> end
> 1
> 1.2
> 1.4
> 1.6
> 1.8
> 2
> 2.2
> 2.4
> 2.6
> 2.8
> 3
> 3.2
> 3.4
> 3.6
> 3.8
> 4
> 4.2
> 4.4
> 4.6
> 4.8
> 5
> How do I ensure I only keep the whole numbers? Using the following would not be ideal (keep if inlist(end, 1,2,3,4,5)) as I may have a much longer list.
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