solver:how_do_i_fix_a_semiint_cont_variable

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solver:how_do_i_fix_a_semiint_cont_variable [2010/05/19 11:07] support |
solver:how_do_i_fix_a_semiint_cont_variable [2010/05/19 11:07] (current) support |
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* Solved as an RMIP the domain of x becomes {1} | * Solved as an RMIP the domain of x becomes {1} | ||

x.fx=1; solve m us rmip min z; abort$(abs(z.l-1)>1e-6) 'wrong obj'; | x.fx=1; solve m us rmip min z; abort$(abs(z.l-1)>1e-6) 'wrong obj'; | ||

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* Solved as a MIP with x.prior=INF the domain of x becomes also {1} | * Solved as a MIP with x.prior=INF the domain of x becomes also {1} | ||

x.fx=1; x.prior=INF; solve m us mip min z; abort$(abs(z.l-1)>1e-6) 'wrong obj'; | x.fx=1; x.prior=INF; solve m us mip min z; abort$(abs(z.l-1)>1e-6) 'wrong obj'; | ||

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* Since x is not truly fixed (domain is {0,1}) holdfixed does not "hold" x | * Since x is not truly fixed (domain is {0,1}) holdfixed does not "hold" x | ||

x.fx=1; m.holdfixed=1; solve m us mip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | x.fx=1; m.holdfixed=1; solve m us mip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | ||

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* Holdfixed does not "hold" semicont variables even if they are relaxed and truely fixed | * Holdfixed does not "hold" semicont variables even if they are relaxed and truely fixed | ||

x.fx=1; m.holdfixed=1; solve m us rmip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | x.fx=1; m.holdfixed=1; solve m us rmip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | ||

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* Holdfixed does not "hold" semicont variables even if they are relaxed and truly fixed | * Holdfixed does not "hold" semicont variables even if they are relaxed and truly fixed | ||

x.fx=1; x.prior=INF; m.holdfixed=1; solve m us mip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | x.fx=1; x.prior=INF; m.holdfixed=1; solve m us mip min z; abort$(m.numvar<>2) 'x hold incorrectly'; | ||

</code> | </code> |

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solver/how_do_i_fix_a_semiint_cont_variable.txt ยท Last modified: 2010/05/19 11:07 by support