Basic Feasible Solutions, Basic Solutions and Optimal Solution The 2019 Stack Overflow Developer Survey Results Are InAre these solutions to a LP problem feasible? basic?Finding all basic feasible solutions in a linear programFind all optimal solutions by SimplexHow to test if a feasible solution is optimal - Complementary Slackness Theorem - Linear ProgrammingSimplex method - multiple optimal solutions?How to find all basic feasible solutions of a linear system?Primal-Dual basic (feasible) solution?Problem regarding a LPP can have a non-basic optimal solutionBasic Feasible solution And Optimality condition
Why is my p-value correlated to difference between means in two sample tests?
Dual Citizen. Exited the US on Italian passport recently
What is the best strategy for white in this position?
If a poisoned arrow's piercing damage is reduced to 0, do you still get poisoned?
Is there a name of the flying bionic bird?
What is the motivation for a law requiring 2 parties to consent for recording a conversation
Manuscript was "unsubmitted" because the manuscript was deposited in Arxiv Preprints
Is "plugging out" electronic devices an American expression?
Lethal sonic weapons
In microwave frequencies, do you use a circulator when you need a (near) perfect diode?
Does duplicating a spell with Wish count as casting that spell?
What is a mixture ratio of propellant?
What does "rabbited" mean/imply in this sentence?
Pristine Bit Checking
Landlord wants to switch my lease to a "Land contract" to "get back at the city"
Idiomatic way to prevent slicing?
How to make payment on the internet without leaving a money trail?
Where does the "burst of radiance" from Holy Weapon originate?
What does "sndry explns" mean in one of the Hitchhiker's guide books?
Are USB sockets on wall outlets live all the time, even when the switch is off?
Inline version of a function returns different value than non-inline version
On the insanity of kings as an argument against monarchy
A poker game description that does not feel gimmicky
What function has this graph?
Basic Feasible Solutions, Basic Solutions and Optimal Solution
The 2019 Stack Overflow Developer Survey Results Are InAre these solutions to a LP problem feasible? basic?Finding all basic feasible solutions in a linear programFind all optimal solutions by SimplexHow to test if a feasible solution is optimal - Complementary Slackness Theorem - Linear ProgrammingSimplex method - multiple optimal solutions?How to find all basic feasible solutions of a linear system?Primal-Dual basic (feasible) solution?Problem regarding a LPP can have a non-basic optimal solutionBasic Feasible solution And Optimality condition
$begingroup$
I'm currently studying linear programming and I came across this MIT resource. In the very first page of the pdf, under BT Exercise 2.10 the 6th statement reads:
- Consider the problem of minimizing maxc’x, d’x over the set P. If
this problem has an optimal solution, it must have an optimal solution
which is an extreme point of P.
And on the next page, the solution manual author claims that the above statement is false and proceeds to provide a counter-example:
- False. Consider the problem of minimizing $x_1−0.5 = maxx_1−0.5x_3, −x_1+ 0.5x_3$ subject to $x_1+x_2 = 1, x_3 = 1$ and $x_1 + x_2 = 1, x_3 = 1$ and $(x_1,x_2,x_3) ≥ (0, 0, 0)$. Its unique optimal solution is $(x_1, x_2, x_3) =
> (0.5, 0.5, 1)$ which is not a BFS.
This confuses me. I was under the impression that extreme points are the same as basic solutions. Is this true?
If it is true and if one of basic solutions is not the optimal solution, then what is even the point of calculating the basic solutions? What am I missing here? Any help to get out of this confusion is appreciated!
linear-programming
$endgroup$
add a comment |
$begingroup$
I'm currently studying linear programming and I came across this MIT resource. In the very first page of the pdf, under BT Exercise 2.10 the 6th statement reads:
- Consider the problem of minimizing maxc’x, d’x over the set P. If
this problem has an optimal solution, it must have an optimal solution
which is an extreme point of P.
And on the next page, the solution manual author claims that the above statement is false and proceeds to provide a counter-example:
- False. Consider the problem of minimizing $x_1−0.5 = maxx_1−0.5x_3, −x_1+ 0.5x_3$ subject to $x_1+x_2 = 1, x_3 = 1$ and $x_1 + x_2 = 1, x_3 = 1$ and $(x_1,x_2,x_3) ≥ (0, 0, 0)$. Its unique optimal solution is $(x_1, x_2, x_3) =
> (0.5, 0.5, 1)$ which is not a BFS.
This confuses me. I was under the impression that extreme points are the same as basic solutions. Is this true?
If it is true and if one of basic solutions is not the optimal solution, then what is even the point of calculating the basic solutions? What am I missing here? Any help to get out of this confusion is appreciated!
linear-programming
$endgroup$
add a comment |
$begingroup$
I'm currently studying linear programming and I came across this MIT resource. In the very first page of the pdf, under BT Exercise 2.10 the 6th statement reads:
- Consider the problem of minimizing maxc’x, d’x over the set P. If
this problem has an optimal solution, it must have an optimal solution
which is an extreme point of P.
And on the next page, the solution manual author claims that the above statement is false and proceeds to provide a counter-example:
- False. Consider the problem of minimizing $x_1−0.5 = maxx_1−0.5x_3, −x_1+ 0.5x_3$ subject to $x_1+x_2 = 1, x_3 = 1$ and $x_1 + x_2 = 1, x_3 = 1$ and $(x_1,x_2,x_3) ≥ (0, 0, 0)$. Its unique optimal solution is $(x_1, x_2, x_3) =
> (0.5, 0.5, 1)$ which is not a BFS.
This confuses me. I was under the impression that extreme points are the same as basic solutions. Is this true?
If it is true and if one of basic solutions is not the optimal solution, then what is even the point of calculating the basic solutions? What am I missing here? Any help to get out of this confusion is appreciated!
linear-programming
$endgroup$
I'm currently studying linear programming and I came across this MIT resource. In the very first page of the pdf, under BT Exercise 2.10 the 6th statement reads:
- Consider the problem of minimizing maxc’x, d’x over the set P. If
this problem has an optimal solution, it must have an optimal solution
which is an extreme point of P.
And on the next page, the solution manual author claims that the above statement is false and proceeds to provide a counter-example:
- False. Consider the problem of minimizing $x_1−0.5 = maxx_1−0.5x_3, −x_1+ 0.5x_3$ subject to $x_1+x_2 = 1, x_3 = 1$ and $x_1 + x_2 = 1, x_3 = 1$ and $(x_1,x_2,x_3) ≥ (0, 0, 0)$. Its unique optimal solution is $(x_1, x_2, x_3) =
> (0.5, 0.5, 1)$ which is not a BFS.
This confuses me. I was under the impression that extreme points are the same as basic solutions. Is this true?
If it is true and if one of basic solutions is not the optimal solution, then what is even the point of calculating the basic solutions? What am I missing here? Any help to get out of this confusion is appreciated!
linear-programming
linear-programming
edited Nov 1 '18 at 14:18
PPGoodMan
asked Nov 1 '18 at 14:10
PPGoodManPPGoodMan
757
757
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
$(0.5,0.5,1)$ is not a BFS and it is also not an extreme point of $P$. There are only $2$ independent constraints that are active.
Notice that $$min_x_1,x_2,x_3 max x_1 -0.5, -x_1+0.5$$
subject to $$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
is not a linear programming problem.
However, it can be converted to a linear programming problem.
$$min_x_1,x_2,x_3,z z$$
subject to
$$z ge x_1 - 0.5$$
$$z ge -x_1+0.5$$
$$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
Notice that $4$ independent constraints are active. The BFS in the new feasible set is $(0.5,0.5,1,0)$
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
return StackExchange.using("mathjaxEditing", function ()
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
);
);
, "mathjax-editing");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "69"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2980459%2fbasic-feasible-solutions-basic-solutions-and-optimal-solution%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
$(0.5,0.5,1)$ is not a BFS and it is also not an extreme point of $P$. There are only $2$ independent constraints that are active.
Notice that $$min_x_1,x_2,x_3 max x_1 -0.5, -x_1+0.5$$
subject to $$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
is not a linear programming problem.
However, it can be converted to a linear programming problem.
$$min_x_1,x_2,x_3,z z$$
subject to
$$z ge x_1 - 0.5$$
$$z ge -x_1+0.5$$
$$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
Notice that $4$ independent constraints are active. The BFS in the new feasible set is $(0.5,0.5,1,0)$
$endgroup$
add a comment |
$begingroup$
$(0.5,0.5,1)$ is not a BFS and it is also not an extreme point of $P$. There are only $2$ independent constraints that are active.
Notice that $$min_x_1,x_2,x_3 max x_1 -0.5, -x_1+0.5$$
subject to $$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
is not a linear programming problem.
However, it can be converted to a linear programming problem.
$$min_x_1,x_2,x_3,z z$$
subject to
$$z ge x_1 - 0.5$$
$$z ge -x_1+0.5$$
$$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
Notice that $4$ independent constraints are active. The BFS in the new feasible set is $(0.5,0.5,1,0)$
$endgroup$
add a comment |
$begingroup$
$(0.5,0.5,1)$ is not a BFS and it is also not an extreme point of $P$. There are only $2$ independent constraints that are active.
Notice that $$min_x_1,x_2,x_3 max x_1 -0.5, -x_1+0.5$$
subject to $$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
is not a linear programming problem.
However, it can be converted to a linear programming problem.
$$min_x_1,x_2,x_3,z z$$
subject to
$$z ge x_1 - 0.5$$
$$z ge -x_1+0.5$$
$$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
Notice that $4$ independent constraints are active. The BFS in the new feasible set is $(0.5,0.5,1,0)$
$endgroup$
$(0.5,0.5,1)$ is not a BFS and it is also not an extreme point of $P$. There are only $2$ independent constraints that are active.
Notice that $$min_x_1,x_2,x_3 max x_1 -0.5, -x_1+0.5$$
subject to $$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
is not a linear programming problem.
However, it can be converted to a linear programming problem.
$$min_x_1,x_2,x_3,z z$$
subject to
$$z ge x_1 - 0.5$$
$$z ge -x_1+0.5$$
$$x_1+x_2=1$$
$$x_3=1$$
$$xge 0$$
Notice that $4$ independent constraints are active. The BFS in the new feasible set is $(0.5,0.5,1,0)$
answered Nov 1 '18 at 14:59
Siong Thye GohSiong Thye Goh
104k1468120
104k1468120
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2980459%2fbasic-feasible-solutions-basic-solutions-and-optimal-solution%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown