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04-30-2008 12:22 AM

I find that the "bounds" takes no roles in "proc model" or programming. The following is an example. I want to get the positive solution. But it gives the negative one. Dose anybody has any suggestion?

Notes: (1)You can impose the initial value of x=5. But in general, you do not know the solution and so it is very difficutlt to give a close initial values.

(2)You can replace x by exp(x). But it makes the computing more difficult and sometimes can not get the solution.

data aaaa;

b2=1; b1=-4; b3=-5;

run;

proc model data=aaaa out=ab_1 noprint;

bounds x>0;

dependent x 1;

eq.eq1=b2*x**2+b1*x+b3;

solve x /converge=1e-6 maxiter=200;

run; Message was edited by: HHBB

Notes: (1)You can impose the initial value of x=5. But in general, you do not know the solution and so it is very difficutlt to give a close initial values.

(2)You can replace x by exp(x). But it makes the computing more difficult and sometimes can not get the solution.

data aaaa;

b2=1; b1=-4; b3=-5;

run;

proc model data=aaaa out=ab_1 noprint;

bounds x>0;

dependent x 1;

eq.eq1=b2*x**2+b1*x+b3;

solve x /converge=1e-6 maxiter=200;

run; Message was edited by: HHBB

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05-27-2008 04:58 PM

PROC MODEL is part of SAS/ETS. If you pose your question in the SAS Forecasting forum

http://support.sas.com/forums/forum.jspa?forumID=28

they should be able to help.

http://support.sas.com/forums/forum.jspa?forumID=28

they should be able to help.