degeneracy and duality in linear programming











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I'm currently learning about linear programming and optimization methods and the most recent subject was duality



I'm trying to understand the connection between degeneracy of the primal and properties of the dual.



We were told in lecture (at least for the case of standard linear programming) that if the primal is non-degenerate then the dual has a unique optimal solution. But this statement wasn't prove and I wasn't able to prove it by myself



I would appreciate some assistant



just to be clear the standard form requires to $min(c^t cdot x)$ subject to $Acdot x = b$ and $xgeq 0$










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    up vote
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    favorite
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    I'm currently learning about linear programming and optimization methods and the most recent subject was duality



    I'm trying to understand the connection between degeneracy of the primal and properties of the dual.



    We were told in lecture (at least for the case of standard linear programming) that if the primal is non-degenerate then the dual has a unique optimal solution. But this statement wasn't prove and I wasn't able to prove it by myself



    I would appreciate some assistant



    just to be clear the standard form requires to $min(c^t cdot x)$ subject to $Acdot x = b$ and $xgeq 0$










    share|cite|improve this question


























      up vote
      1
      down vote

      favorite
      1









      up vote
      1
      down vote

      favorite
      1






      1





      I'm currently learning about linear programming and optimization methods and the most recent subject was duality



      I'm trying to understand the connection between degeneracy of the primal and properties of the dual.



      We were told in lecture (at least for the case of standard linear programming) that if the primal is non-degenerate then the dual has a unique optimal solution. But this statement wasn't prove and I wasn't able to prove it by myself



      I would appreciate some assistant



      just to be clear the standard form requires to $min(c^t cdot x)$ subject to $Acdot x = b$ and $xgeq 0$










      share|cite|improve this question















      I'm currently learning about linear programming and optimization methods and the most recent subject was duality



      I'm trying to understand the connection between degeneracy of the primal and properties of the dual.



      We were told in lecture (at least for the case of standard linear programming) that if the primal is non-degenerate then the dual has a unique optimal solution. But this statement wasn't prove and I wasn't able to prove it by myself



      I would appreciate some assistant



      just to be clear the standard form requires to $min(c^t cdot x)$ subject to $Acdot x = b$ and $xgeq 0$







      optimization linear-programming duality-theorems






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      share|cite|improve this question













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      edited Nov 14 at 18:57

























      asked Nov 14 at 18:43









      user615821

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          Let $x in mathbb{R}^n$ and $A in mathbb{R}^{m times n}$ where the rows of $A$ are linearly independent.



          Suppose it is nondegenerate, then there are $m$ components of $x$ which are positive. Denote the set of such indices to be $B$.



          By complementary slackness condition,
          $$forall i in B, x_i(p^TA_i-c_i)=0$$



          $$forall i in B, p^TA_i=c_i$$



          Notice that the columns of $A_i$ where $i in B$ are linearly independent, hence we can solve for $p$ uniquely.






          share|cite|improve this answer





















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            Let $x in mathbb{R}^n$ and $A in mathbb{R}^{m times n}$ where the rows of $A$ are linearly independent.



            Suppose it is nondegenerate, then there are $m$ components of $x$ which are positive. Denote the set of such indices to be $B$.



            By complementary slackness condition,
            $$forall i in B, x_i(p^TA_i-c_i)=0$$



            $$forall i in B, p^TA_i=c_i$$



            Notice that the columns of $A_i$ where $i in B$ are linearly independent, hence we can solve for $p$ uniquely.






            share|cite|improve this answer

























              up vote
              0
              down vote













              Let $x in mathbb{R}^n$ and $A in mathbb{R}^{m times n}$ where the rows of $A$ are linearly independent.



              Suppose it is nondegenerate, then there are $m$ components of $x$ which are positive. Denote the set of such indices to be $B$.



              By complementary slackness condition,
              $$forall i in B, x_i(p^TA_i-c_i)=0$$



              $$forall i in B, p^TA_i=c_i$$



              Notice that the columns of $A_i$ where $i in B$ are linearly independent, hence we can solve for $p$ uniquely.






              share|cite|improve this answer























                up vote
                0
                down vote










                up vote
                0
                down vote









                Let $x in mathbb{R}^n$ and $A in mathbb{R}^{m times n}$ where the rows of $A$ are linearly independent.



                Suppose it is nondegenerate, then there are $m$ components of $x$ which are positive. Denote the set of such indices to be $B$.



                By complementary slackness condition,
                $$forall i in B, x_i(p^TA_i-c_i)=0$$



                $$forall i in B, p^TA_i=c_i$$



                Notice that the columns of $A_i$ where $i in B$ are linearly independent, hence we can solve for $p$ uniquely.






                share|cite|improve this answer












                Let $x in mathbb{R}^n$ and $A in mathbb{R}^{m times n}$ where the rows of $A$ are linearly independent.



                Suppose it is nondegenerate, then there are $m$ components of $x$ which are positive. Denote the set of such indices to be $B$.



                By complementary slackness condition,
                $$forall i in B, x_i(p^TA_i-c_i)=0$$



                $$forall i in B, p^TA_i=c_i$$



                Notice that the columns of $A_i$ where $i in B$ are linearly independent, hence we can solve for $p$ uniquely.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 15 at 2:58









                Siong Thye Goh

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                94.3k1462114






























                     

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