Re: st: drop observations - if statement

[Jeph Herrin <info@flyingbuttress.net>]

Are you sure any are missing?

Try

 count if missing(cusip)

and see what you get.

hth,
Jeph



On 3/5/2014 5:41 PM, R Zhang wrote:
> Hi all,
>
> I used the following commands to drop observations based on a string
> variable - CUSIP- that takes missing values, i.e. delete observations
> with missing CUSIP,
>
> drop if cusip==""
>
> cusip is str10
>
> (0 observations deleted)
>
> could you explain why "(0 observations deleted)"?
>
> thanks,
>
> Rochelle
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