Re: st: Problem with "If" statement

[Keith Dear <keith.dear@anu.edu.au>]

Deepankar,
You don't need either sort of -if-.  Try it like this instead:
gen byte p`size'`alive' = cond(`size'==`alive', 100, 10)
Moreover there is then no need to initialise the pxy variables.
kd

At 03:51 PM 5/6/06, you wrote:
> I am facing problems using the "if" statement (not the "if" 
> qualifier) because the expression in the "if" statement has a 
> variable. Hence, the commands are being executed taking only the 
> first observation of the variable. What is the way to execute the 
> commands for all the observations? I give a details of a prototype 
> (simplified) problem below.
>
> I have two variables x and y. Each can take values 1 or 2. And I 
> have four more variables p11, p12, p21 and p22. I want to go down 
> each observation of x, compare it to y and if they are equal then 
> make p`x'`y'=100, otherwise make p`x'`y'=10.
>
> To do the above task, I write the following program:
> ++++++++++++++++++++++++++++++++++++++
> capture program drop rpc
> program define rpc
> version 8.0
> args size alive
> if `size'==`alive'  {
>   replace p`size'`alive'=100
> }
> else  {
>   replace p`size'`alive'=10
> }
> end
> ++++++++++++++++++++++++++++++++++++
>
> I run this program and then run the following do-file:
>
> +++++++++++++++++++++++++++++++++++
> set more 1
> version 8.0
> local i 1
> while `i' <=2  {
>   local j 2
>   while `j' <= `i'  {
>     gen p`i'`j'=0
>     local j = `j' + 1
>   }
>   local i = `i' + 1
> }
>
> rpc x y
>
> +++++++++++++++++++++++++++++++++++++
>
>
> My problem is that I cannot get the program to go through each 
> observation on x and y. It takes the first observation of x and y 
> and stops there. It does not move to the next observation.
>
> Any suggestions on how to tackle this issue will be greatly appreciated.
>
> Deepankar
>
>
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