Constraints in NGene

[mires]

Hi All,


I want to constraint two contunous attrbutes, one to be greater than 1.15 the secund, and lesser than twice the secund
;require:
alt1.premium1 > 1.15 * alt1.confort1,
alt1.premium1 < 1.5 * alt1.confort1,

NGene is not accepting such constraint, any idea , a tick to overcome such issue?

Thanks a lot
Naji

[johnr]

Hi Naji

Unfortunately, the require and conditional commands are incompatible with the Nelder Mead algorithm. There is no work around for this at the moment that I can see.

John

[tn73]

Hi all
I would like to constrain the attribute levels (percentages) in each alternative (fuel mix) such that they to sum up to 100%. I have tried the syntax below but I get an error: "Error: The ';alg' property contains an unrecognised algorithm type. 'mfederov'

When I remove the alg property, the model runs but none of the alternatives generated meet the constraint.

;alts = alt1, alt2, alt3
;rows = 12
;eff = (mnl,d)
;alg = mfederov
;require:
alt1.Hydro + alt1.Coal + alt1.Geo + alt1.Wind + alt1.Gas = 100,
alt2.Hydro + alt2.Coal + alt2.Geo + alt2.Wind + alt2.Gas = 100
;model:
U(alt1) = b_Hydro[0.0772] * Hydro[0,10,20,30] + b_Coal[-0.028] * Coal[0,10,20,30] + b_Geo[0.0465] * Geo[0,10,20,30] + b_Wind[0.0784] * Wind[20,40,60,80] + b_Gas[-0.0014] * Gas[0,20,40,60] + b_Cost[-0.0066] *Cost[5,10,15,20] /
U(alt2) = b_Hydro * Hydro + b_Coal * Coal + b_Geo * Geo + b_Wind * Wind + b_Gas * Gas + b_Cost * Cost $

Please help
tn73