Dear Listers,
I have the following dataset
input a b
1 2
1 3
1 4
1 5
1 6
1 7
1 8
2 3
2 4
2 5
2 6
2 7
2 8
3 4
3 5
3 6
3 7
3 8
4 5
4 6
4 7
4 8
5 6
5 7
5 8
6 7
6 8
7 8
end
save a1,replace
and I need to find the code capable of distributing it in seven groups ,of
four observations (pairs of numbers) each ,such that each group would have
eight numbers and no group may contain any repeating number
and no pair of numbers may be repetitive within the seven groups.For example
:
1 2,3 4,5 6,7 8
1 3,2 6,3 7,4 8
.........................
.........................
.........................
........................
1 8,2 7,3 6,4 5
I have written the following code but a loop of two million could do less
than half of the job ..... ..
drop _all
set more off
set obs 1120
gen a = .
gen b = .
gen n = .
local i = 1
while `i'<= 16 {
local e = 1
while `e'<= 16 {
local n = [`i'-1]* 16 + `e'
replace a = `i' in `n'
replace b = `e' in `n'
replace n = `n' in `n'
local e = `e'+1
}
local i = `i'+1
}
drop if a>=b
replace n = _n
sort n
save a1,replace
local i = 1
while `i'<= 2000000 {
use a1,clear
di in yellow " " _N " " `i'
sample 8,count
save a2,replace
keep a
gen n = _n
sort n
save a3,replace
use a2,clear
keep b
rename b a
gen n = _n+8
sort n
merge n using a3
drop _merge
sort a
drop if a[_n]==a[_n-1]
if _N==16 {
use a2,clear
save ada`i',replace
sort n
merge n using a1
drop if _merge==3
drop _merge
sort n
save a1,replace
if _N==8 {
save adalast
}
if _N==8 {
exit
}
}
local i = `i'+1
}
dir
If anyone can tell me of a smarter code I would appreciate it greatly ,for I
have been banging my head at this for the past two weeks.
I thank you in advance ,
Victor M. Zammit
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