Re: st: search the dataset for a string value

[Roger Newson <roger.newson@kcl.ac.uk>]

At 16:07 23/02/04 +0000, Paul O'Brien wrote:
> The help on -index- leaves me a bit ignorant.
>
> I use this without knowing how it works:
>
> gen oral = "OVYS" if index(stk,"OVYS")
> replace oral = "MICROG" if index(stk, "MICROG")
> replace oral ="FEMOD" if index(stk, "FEMOD")
> replace oral = "LOGED" if index(stk, "LOGED")
>
> Index 'returns the position' it finds the string'
>
> The position of MICROG could be,  say, 9th character  to 14th in the 
> string and returns 9-14. How is this translated in a yes?
The -index()- function evaluates to zero if the second argument appears 
nowhere in the first argument. And -if- treats zero value as "no", and 
treats all nonzero numeric values (including negative and missing values) 
as "yes". See -help ifcmd- and -help if- for further references.

Roger


--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
King's College London
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Opinions expressed are those of the author, not the institution.

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