Set of Feasible DirectionsAre these solutions to a LP problem feasible? basic?Construct a linear programming problem for which both the primal and the dual problem has no feasible solutionFinding all basic feasible solutions in a linear programWhat's a basic solution, and how do we find them?How can I determine feasability / optimality given a set of variables?Why feasible set of LP is a polyhedronBasic solution, basic feasible solution, degeneracyExtreme directions of $S=x:-x_1+2x_2le 4,x_1-3x_2le 3,x_1,x_2ge 0$Finding cones of directionsHow to find an extreme feasible point in a linear polytope (set $x : Ax leq b$ defined by halfspaces)?
Is ipsum/ipsa/ipse a third person pronoun, or can it serve other functions?
New order #4: World
Calculate Levenshtein distance between two strings in Python
Typesetting a double Over Dot on top of a symbol
What to wear for invited talk in Canada
Why was the "bread communication" in the arena of Catching Fire left out in the movie?
Find the positive root of a 4-th degree polynomial equation
What are the advantages and disadvantages of running one shots compared to campaigns?
Is this food a bread or a loaf?
"My colleague's body is amazing"
aging parents with no investments
Shall I use personal or official e-mail account when registering to external websites for work purpose?
Unbreakable Formation vs. Cry of the Carnarium
Can a planet have a different gravitational pull depending on its location in orbit around its sun?
Why doesn't a const reference extend the life of a temporary object passed via a function?
LWC and complex parameters
How to move the player while also allowing forces to affect it
Symmetry in quantum mechanics
Why is my log file so massive? 22gb. I am running log backups
Information to fellow intern about hiring?
What is the command to reset a PC without deleting any files
extract characters between two commas?
Could a US political party gain complete control over the government by removing checks & balances?
Does bootstrapped regression allow for inference?
Set of Feasible Directions
Are these solutions to a LP problem feasible? basic?Construct a linear programming problem for which both the primal and the dual problem has no feasible solutionFinding all basic feasible solutions in a linear programWhat's a basic solution, and how do we find them?How can I determine feasability / optimality given a set of variables?Why feasible set of LP is a polyhedronBasic solution, basic feasible solution, degeneracyExtreme directions of $S=x:-x_1+2x_2le 4,x_1-3x_2le 3,x_1,x_2ge 0$Finding cones of directionsHow to find an extreme feasible point in a linear polytope (set $x : Ax leq b$ defined by halfspaces)?
$begingroup$
I don't even know what to do for the first part. How do you even find all the feasible directions of a particular Set...?
Then how do you proceed to finding basic directions?
linear-programming
$endgroup$
add a comment |
$begingroup$
I don't even know what to do for the first part. How do you even find all the feasible directions of a particular Set...?
Then how do you proceed to finding basic directions?
linear-programming
$endgroup$
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10
add a comment |
$begingroup$
I don't even know what to do for the first part. How do you even find all the feasible directions of a particular Set...?
Then how do you proceed to finding basic directions?
linear-programming
$endgroup$
I don't even know what to do for the first part. How do you even find all the feasible directions of a particular Set...?
Then how do you proceed to finding basic directions?
linear-programming
linear-programming
asked Nov 27 '15 at 1:02
llllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
3419
3419
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10
add a comment |
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
Use the definition of a feasible direction $d$ at $(0,0,1)$: $(0,0,1)+theta din P$ for all $thetain (0,delta)$ for some $delta>0$ if and only if $theta d_1 +theta d_2 +1+theta d_3=1$ and $theta d_1geq 0$, $theta d_2geq 0$ and $1+theta d_3geq 0$ for all $thetain (0,delta)$. Since $thetain (0,delta)$, this is equivalent to $$d_1+d_2+d_3=0,quad d_1,d_2geq 0,quad theta d_3geq -1$$ for all $thetain (0,delta)$. This defines the feasible directions.
$endgroup$
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%2f1548039%2fset-of-feasible-directions%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
$begingroup$
Use the definition of a feasible direction $d$ at $(0,0,1)$: $(0,0,1)+theta din P$ for all $thetain (0,delta)$ for some $delta>0$ if and only if $theta d_1 +theta d_2 +1+theta d_3=1$ and $theta d_1geq 0$, $theta d_2geq 0$ and $1+theta d_3geq 0$ for all $thetain (0,delta)$. Since $thetain (0,delta)$, this is equivalent to $$d_1+d_2+d_3=0,quad d_1,d_2geq 0,quad theta d_3geq -1$$ for all $thetain (0,delta)$. This defines the feasible directions.
$endgroup$
add a comment |
$begingroup$
Use the definition of a feasible direction $d$ at $(0,0,1)$: $(0,0,1)+theta din P$ for all $thetain (0,delta)$ for some $delta>0$ if and only if $theta d_1 +theta d_2 +1+theta d_3=1$ and $theta d_1geq 0$, $theta d_2geq 0$ and $1+theta d_3geq 0$ for all $thetain (0,delta)$. Since $thetain (0,delta)$, this is equivalent to $$d_1+d_2+d_3=0,quad d_1,d_2geq 0,quad theta d_3geq -1$$ for all $thetain (0,delta)$. This defines the feasible directions.
$endgroup$
add a comment |
$begingroup$
Use the definition of a feasible direction $d$ at $(0,0,1)$: $(0,0,1)+theta din P$ for all $thetain (0,delta)$ for some $delta>0$ if and only if $theta d_1 +theta d_2 +1+theta d_3=1$ and $theta d_1geq 0$, $theta d_2geq 0$ and $1+theta d_3geq 0$ for all $thetain (0,delta)$. Since $thetain (0,delta)$, this is equivalent to $$d_1+d_2+d_3=0,quad d_1,d_2geq 0,quad theta d_3geq -1$$ for all $thetain (0,delta)$. This defines the feasible directions.
$endgroup$
Use the definition of a feasible direction $d$ at $(0,0,1)$: $(0,0,1)+theta din P$ for all $thetain (0,delta)$ for some $delta>0$ if and only if $theta d_1 +theta d_2 +1+theta d_3=1$ and $theta d_1geq 0$, $theta d_2geq 0$ and $1+theta d_3geq 0$ for all $thetain (0,delta)$. Since $thetain (0,delta)$, this is equivalent to $$d_1+d_2+d_3=0,quad d_1,d_2geq 0,quad theta d_3geq -1$$ for all $thetain (0,delta)$. This defines the feasible directions.
edited Nov 26 '16 at 21:31
answered Nov 26 '16 at 10:27
AnonymousIGuessAnonymousIGuess
1519
1519
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%2f1548039%2fset-of-feasible-directions%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
$begingroup$
$x = (0,0,1)$ is a point on the boundary of $P$ (note that $0 + 0 + 1 = 1$). From the definition of feasible direction, in this case, it means a direction that points into $P$, instead of outside. Hint: this $P$ lines within a plane (and if I am correct in interpreting "$x ge 0$" to mean $x_1 ge 0, x_2 ge 0, x_3 ge 0$, then $P$ is a triangle in that plane, with $x$ as one of its vertices).
$endgroup$
– Paul Sinclair
Nov 27 '15 at 5:10