Statalist


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: Resetting the local in a nested loop


From   Phil Schumm <pschumm@uchicago.edu>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Resetting the local in a nested loop
Date   Wed, 19 Aug 2009 06:03:23 -0500

On Aug 19, 2009, at 4:08 AM, Michael Stuetzer wrote:
I have a small problem with a nested loop and maybe you can give me an advice. For a specific business starting activity I have data for the beginning (BUSINESSPLAN_SP[odd]) and the end (BUSINESSPLAN_SP[even]) of this activity. For instance the entrepreneur worked on the business plan in the months 4 till 7 as well as 16 till 25. I want to transfer the information into a time grid. In this grid t1, t2, etc. stands for the respective month. They should take the value of 1 if the entrepreneur worked on the business plan on the point of time. I have here a first draft of the loop.


set more off
local r=5
forvalues i=1/100 {
	local j=1
	local k=`j'+1
	while `j'<=`r' {
		replace t`i' = 1 BUSINESSPLAN_SP`j'<=`i' & BUSINESSPLAN_SP`k'>=`i'
		local j=`j'+1
		}
	}

The problem is that this loop recognizes the first sequence (4 to 7), but not the second sequence (16 to 25). I suspect something is wrong with the resetting of the local j (local j=`j'+1) and k.


I presume from your code that you have the variables BUSINESSPLAN_SP1- BUSINESSPLAN_SP6, that you've verified that no one worked on their business plan beyond month 100, and that you've already generated the variables t1-t100 set to 0. Your code should read:


local r=5
forv i=1/100 {
    local j=1
    while `j'<=`r' {
        local k=`j'+1  // moved from above
replace t`i' = 1 if BUSINESSPLAN_SP`j'<=`i' & BUSINESSPLAN_SP`k'>=`i'
        local j=`j'+2  // changed
    }
}


Note that you need to increment k within your -while- loop, and you need to increment j by 2 (instead of 1). If you haven't already, you might also want to verify the following:


forv i = 1/5 {
    ass BUSINESSPLAN_SP`i' <= BUSINESSPLAN_SP`=`i'+1'
}


-- Phil

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index