NMaximize is not converging to a solution












3












$begingroup$


I am trying to use NMaximize to find the maximum value of a variable that satisfies the given constraints. Since the constraints aren't straightforward, I am using the function.



I can see the constraints are such that the value is bounded but I get the below warning messages:




NMaximize::cvmit: Failed to converge to the requested accuracy or
precision within 100000 iterations.



NMaximize::cvdiv: Failed to
converge to a solution. The function may be unbounded.




The constraint and the way I am using the function is as below:



    constraint = (x | y) [Element] 
Integers && ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. &&
0 <= y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x -
3.63201*10^84 x^2]) || (10713. <= x <= 19762. &&
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2] < y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2]))


maxX =
NMaximize[{x, constraint}, {x, y}, MaxIterations -> 100000]


I have increased the MaxIterations from 100 to 100000 but it doesn't seem to converge. I am not sure if increasing the MaxIterations is the solution. Can you please guide me with this?










share|improve this question









$endgroup$












  • $begingroup$
    Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
    $endgroup$
    – Daniel Lichtblau
    yesterday






  • 1




    $begingroup$
    I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
    $endgroup$
    – JimB
    yesterday












  • $begingroup$
    @JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
    $endgroup$
    – gaganso
    yesterday










  • $begingroup$
    Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
    $endgroup$
    – JimB
    yesterday








  • 1




    $begingroup$
    OK. I was assuming that you were conditioning on the maximum value of $x$.
    $endgroup$
    – JimB
    yesterday
















3












$begingroup$


I am trying to use NMaximize to find the maximum value of a variable that satisfies the given constraints. Since the constraints aren't straightforward, I am using the function.



I can see the constraints are such that the value is bounded but I get the below warning messages:




NMaximize::cvmit: Failed to converge to the requested accuracy or
precision within 100000 iterations.



NMaximize::cvdiv: Failed to
converge to a solution. The function may be unbounded.




The constraint and the way I am using the function is as below:



    constraint = (x | y) [Element] 
Integers && ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. &&
0 <= y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x -
3.63201*10^84 x^2]) || (10713. <= x <= 19762. &&
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2] < y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2]))


maxX =
NMaximize[{x, constraint}, {x, y}, MaxIterations -> 100000]


I have increased the MaxIterations from 100 to 100000 but it doesn't seem to converge. I am not sure if increasing the MaxIterations is the solution. Can you please guide me with this?










share|improve this question









$endgroup$












  • $begingroup$
    Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
    $endgroup$
    – Daniel Lichtblau
    yesterday






  • 1




    $begingroup$
    I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
    $endgroup$
    – JimB
    yesterday












  • $begingroup$
    @JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
    $endgroup$
    – gaganso
    yesterday










  • $begingroup$
    Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
    $endgroup$
    – JimB
    yesterday








  • 1




    $begingroup$
    OK. I was assuming that you were conditioning on the maximum value of $x$.
    $endgroup$
    – JimB
    yesterday














3












3








3





$begingroup$


I am trying to use NMaximize to find the maximum value of a variable that satisfies the given constraints. Since the constraints aren't straightforward, I am using the function.



I can see the constraints are such that the value is bounded but I get the below warning messages:




NMaximize::cvmit: Failed to converge to the requested accuracy or
precision within 100000 iterations.



NMaximize::cvdiv: Failed to
converge to a solution. The function may be unbounded.




The constraint and the way I am using the function is as below:



    constraint = (x | y) [Element] 
Integers && ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. &&
0 <= y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x -
3.63201*10^84 x^2]) || (10713. <= x <= 19762. &&
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2] < y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2]))


maxX =
NMaximize[{x, constraint}, {x, y}, MaxIterations -> 100000]


I have increased the MaxIterations from 100 to 100000 but it doesn't seem to converge. I am not sure if increasing the MaxIterations is the solution. Can you please guide me with this?










share|improve this question









$endgroup$




I am trying to use NMaximize to find the maximum value of a variable that satisfies the given constraints. Since the constraints aren't straightforward, I am using the function.



I can see the constraints are such that the value is bounded but I get the below warning messages:




NMaximize::cvmit: Failed to converge to the requested accuracy or
precision within 100000 iterations.



NMaximize::cvdiv: Failed to
converge to a solution. The function may be unbounded.




The constraint and the way I am using the function is as below:



    constraint = (x | y) [Element] 
Integers && ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. &&
0 <= y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x -
3.63201*10^84 x^2]) || (10713. <= x <= 19762. &&
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2] < y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-43 Sqrt[
4.98614*10^92 + 4.65469*10^88 x - 3.63201*10^84 x^2]))


maxX =
NMaximize[{x, constraint}, {x, y}, MaxIterations -> 100000]


I have increased the MaxIterations from 100 to 100000 but it doesn't seem to converge. I am not sure if increasing the MaxIterations is the solution. Can you please guide me with this?







functions maximum






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked yesterday









gagansogaganso

1528




1528












  • $begingroup$
    Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
    $endgroup$
    – Daniel Lichtblau
    yesterday






  • 1




    $begingroup$
    I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
    $endgroup$
    – JimB
    yesterday












  • $begingroup$
    @JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
    $endgroup$
    – gaganso
    yesterday










  • $begingroup$
    Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
    $endgroup$
    – JimB
    yesterday








  • 1




    $begingroup$
    OK. I was assuming that you were conditioning on the maximum value of $x$.
    $endgroup$
    – JimB
    yesterday


















  • $begingroup$
    Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
    $endgroup$
    – Daniel Lichtblau
    yesterday






  • 1




    $begingroup$
    I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
    $endgroup$
    – JimB
    yesterday












  • $begingroup$
    @JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
    $endgroup$
    – gaganso
    yesterday










  • $begingroup$
    Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
    $endgroup$
    – JimB
    yesterday








  • 1




    $begingroup$
    OK. I was assuming that you were conditioning on the maximum value of $x$.
    $endgroup$
    – JimB
    yesterday
















$begingroup$
Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
$endgroup$
– Daniel Lichtblau
yesterday




$begingroup$
Could try maximizing over individual regions of the piecewise set-up. But the machine precision values will make validation of inequalities kind of iffy.
$endgroup$
– Daniel Lichtblau
yesterday




1




1




$begingroup$
I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
$endgroup$
– JimB
yesterday






$begingroup$
I'm not seeing what $y$ has to do with this. Wouldn't the maximum value of $x$ be 19762? constraint /. x -> 19762 results in y [Element] Integers && 7229.16 < y < 7344.29 and constraint /. x -> 19763 results in False.
$endgroup$
– JimB
yesterday














$begingroup$
@JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
$endgroup$
– gaganso
yesterday




$begingroup$
@JimB, I think for x, y isn't needed. Thanks for pointing this out. But if I am trying to maximize y, I need to maximize over both the variables since y is an expression of x, right?
$endgroup$
– gaganso
yesterday












$begingroup$
Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
$endgroup$
– JimB
yesterday






$begingroup$
Yes, if that's what you want. The general solution appears to be $x = 19762$ and $7230leq y leq 7344$. So to maximize $y$ you'd choose $7344$.
$endgroup$
– JimB
yesterday






1




1




$begingroup$
OK. I was assuming that you were conditioning on the maximum value of $x$.
$endgroup$
– JimB
yesterday




$begingroup$
OK. I was assuming that you were conditioning on the maximum value of $x$.
$endgroup$
– JimB
yesterday










2 Answers
2






active

oldest

votes


















5












$begingroup$

Rationalize the constraint:



constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
0 <= y < 2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-1 Sqrt[
4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <= x <=
19762. &&
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) //
Rationalize[#, 0] & // Simplify;


With the Rationalized constraint you can use Maximize:



maxX = Maximize[{x, constraint2}, {x, y}]

(* {19762, {x -> 19762, y -> 7287}} *)

constraint2 /. maxX[[2]]

(* True *)


EDIT: To find maximum y



(maxY = Maximize[{y, constraint2}, {x, y}]) // N


enter image description here



To plot the region defined by the constraint:



reg = ImplicitRegion[constraint2, {x, y}];

Region[reg,
Frame -> True,
FrameLabel -> (Style[#, 12, Bold] & /@ {x, y}),
Epilog -> {Red,
AbsolutePointSize[3],
Point[{x, y} /. maxX[[2]]],
Point[{x, y} /. maxY[[2]]]}]


enter image description here






share|improve this answer











$endgroup$





















    3












    $begingroup$

    You have numbers spread a wide range of magnitudes for no good reason. This range is probably too wide for machine precision arithmetic. Also telling NMinimize explicitly that this an integer optimization problem seems to help. Try this:



    constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
    0 <= y <
    2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
    2.8484*10^-1 Sqrt[
    4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <=
    x <= 19762. &&
    2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
    2.8484*10^-1 Sqrt[
    4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
    2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
    2.8484*10^-1 Sqrt[
    4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) // Expand

    maxX = NMaximize[{x, constraint2}, {x, y}, Integers,
    MaxIterations -> 10000]



    {19762., {x -> 19762, y -> 7311}}




    And with your definition of constraint:



    constraint /. maxX[[2]]



    True







    share|improve this answer











    $endgroup$













    • $begingroup$
      But constraint /. x -> 19762 /. y -> 8647 results in False?
      $endgroup$
      – JimB
      yesterday










    • $begingroup$
      @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
      $endgroup$
      – Henrik Schumacher
      yesterday












    • $begingroup$
      @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
      $endgroup$
      – gaganso
      yesterday












    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: "387"
    };
    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: false,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: null,
    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
    },
    onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    });


    }
    });














    draft saved

    draft discarded


















    StackExchange.ready(
    function () {
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f194684%2fnmaximize-is-not-converging-to-a-solution%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    5












    $begingroup$

    Rationalize the constraint:



    constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
    0 <= y < 2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
    2.8484*10^-1 Sqrt[
    4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <= x <=
    19762. &&
    2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
    2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
    2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
    2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) //
    Rationalize[#, 0] & // Simplify;


    With the Rationalized constraint you can use Maximize:



    maxX = Maximize[{x, constraint2}, {x, y}]

    (* {19762, {x -> 19762, y -> 7287}} *)

    constraint2 /. maxX[[2]]

    (* True *)


    EDIT: To find maximum y



    (maxY = Maximize[{y, constraint2}, {x, y}]) // N


    enter image description here



    To plot the region defined by the constraint:



    reg = ImplicitRegion[constraint2, {x, y}];

    Region[reg,
    Frame -> True,
    FrameLabel -> (Style[#, 12, Bold] & /@ {x, y}),
    Epilog -> {Red,
    AbsolutePointSize[3],
    Point[{x, y} /. maxX[[2]]],
    Point[{x, y} /. maxY[[2]]]}]


    enter image description here






    share|improve this answer











    $endgroup$


















      5












      $begingroup$

      Rationalize the constraint:



      constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
      0 <= y < 2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
      2.8484*10^-1 Sqrt[
      4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <= x <=
      19762. &&
      2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
      2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
      2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
      2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) //
      Rationalize[#, 0] & // Simplify;


      With the Rationalized constraint you can use Maximize:



      maxX = Maximize[{x, constraint2}, {x, y}]

      (* {19762, {x -> 19762, y -> 7287}} *)

      constraint2 /. maxX[[2]]

      (* True *)


      EDIT: To find maximum y



      (maxY = Maximize[{y, constraint2}, {x, y}]) // N


      enter image description here



      To plot the region defined by the constraint:



      reg = ImplicitRegion[constraint2, {x, y}];

      Region[reg,
      Frame -> True,
      FrameLabel -> (Style[#, 12, Bold] & /@ {x, y}),
      Epilog -> {Red,
      AbsolutePointSize[3],
      Point[{x, y} /. maxX[[2]]],
      Point[{x, y} /. maxY[[2]]]}]


      enter image description here






      share|improve this answer











      $endgroup$
















        5












        5








        5





        $begingroup$

        Rationalize the constraint:



        constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
        0 <= y < 2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
        2.8484*10^-1 Sqrt[
        4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <= x <=
        19762. &&
        2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
        2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
        2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
        2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) //
        Rationalize[#, 0] & // Simplify;


        With the Rationalized constraint you can use Maximize:



        maxX = Maximize[{x, constraint2}, {x, y}]

        (* {19762, {x -> 19762, y -> 7287}} *)

        constraint2 /. maxX[[2]]

        (* True *)


        EDIT: To find maximum y



        (maxY = Maximize[{y, constraint2}, {x, y}]) // N


        enter image description here



        To plot the region defined by the constraint:



        reg = ImplicitRegion[constraint2, {x, y}];

        Region[reg,
        Frame -> True,
        FrameLabel -> (Style[#, 12, Bold] & /@ {x, y}),
        Epilog -> {Red,
        AbsolutePointSize[3],
        Point[{x, y} /. maxX[[2]]],
        Point[{x, y} /. maxY[[2]]]}]


        enter image description here






        share|improve this answer











        $endgroup$



        Rationalize the constraint:



        constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
        0 <= y < 2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
        2.8484*10^-1 Sqrt[
        4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <= x <=
        19762. &&
        2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
        2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
        2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
        2.8484*10^-1 Sqrt[4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) //
        Rationalize[#, 0] & // Simplify;


        With the Rationalized constraint you can use Maximize:



        maxX = Maximize[{x, constraint2}, {x, y}]

        (* {19762, {x -> 19762, y -> 7287}} *)

        constraint2 /. maxX[[2]]

        (* True *)


        EDIT: To find maximum y



        (maxY = Maximize[{y, constraint2}, {x, y}]) // N


        enter image description here



        To plot the region defined by the constraint:



        reg = ImplicitRegion[constraint2, {x, y}];

        Region[reg,
        Frame -> True,
        FrameLabel -> (Style[#, 12, Bold] & /@ {x, y}),
        Epilog -> {Red,
        AbsolutePointSize[3],
        Point[{x, y} /. maxX[[2]]],
        Point[{x, y} /. maxY[[2]]]}]


        enter image description here







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited yesterday

























        answered yesterday









        Bob HanlonBob Hanlon

        61.4k33598




        61.4k33598























            3












            $begingroup$

            You have numbers spread a wide range of magnitudes for no good reason. This range is probably too wide for machine precision arithmetic. Also telling NMinimize explicitly that this an integer optimization problem seems to help. Try this:



            constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
            0 <= y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <=
            x <= 19762. &&
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) // Expand

            maxX = NMaximize[{x, constraint2}, {x, y}, Integers,
            MaxIterations -> 10000]



            {19762., {x -> 19762, y -> 7311}}




            And with your definition of constraint:



            constraint /. maxX[[2]]



            True







            share|improve this answer











            $endgroup$













            • $begingroup$
              But constraint /. x -> 19762 /. y -> 8647 results in False?
              $endgroup$
              – JimB
              yesterday










            • $begingroup$
              @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
              $endgroup$
              – Henrik Schumacher
              yesterday












            • $begingroup$
              @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
              $endgroup$
              – gaganso
              yesterday
















            3












            $begingroup$

            You have numbers spread a wide range of magnitudes for no good reason. This range is probably too wide for machine precision arithmetic. Also telling NMinimize explicitly that this an integer optimization problem seems to help. Try this:



            constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
            0 <= y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <=
            x <= 19762. &&
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) // Expand

            maxX = NMaximize[{x, constraint2}, {x, y}, Integers,
            MaxIterations -> 10000]



            {19762., {x -> 19762, y -> 7311}}




            And with your definition of constraint:



            constraint /. maxX[[2]]



            True







            share|improve this answer











            $endgroup$













            • $begingroup$
              But constraint /. x -> 19762 /. y -> 8647 results in False?
              $endgroup$
              – JimB
              yesterday










            • $begingroup$
              @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
              $endgroup$
              – Henrik Schumacher
              yesterday












            • $begingroup$
              @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
              $endgroup$
              – gaganso
              yesterday














            3












            3








            3





            $begingroup$

            You have numbers spread a wide range of magnitudes for no good reason. This range is probably too wide for machine precision arithmetic. Also telling NMinimize explicitly that this an integer optimization problem seems to help. Try this:



            constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
            0 <= y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <=
            x <= 19762. &&
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) // Expand

            maxX = NMaximize[{x, constraint2}, {x, y}, Integers,
            MaxIterations -> 10000]



            {19762., {x -> 19762, y -> 7311}}




            And with your definition of constraint:



            constraint /. maxX[[2]]



            True







            share|improve this answer











            $endgroup$



            You have numbers spread a wide range of magnitudes for no good reason. This range is probably too wide for machine precision arithmetic. Also telling NMinimize explicitly that this an integer optimization problem seems to help. Try this:



            constraint2 = ((x == 0 && 1. <= y <= 12720.) || (1. <= x <= 10712. && 
            0 <= y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2]) || (10713. <=
            x <= 19762. &&
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) -
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2] < y <
            2.08565*10^-36 (3.04959*10^39 + 2.24751*10^34 x) +
            2.8484*10^-1 Sqrt[
            4.98614*10^8 + 4.65469*10^4 x - 3.63201 x^2])) // Expand

            maxX = NMaximize[{x, constraint2}, {x, y}, Integers,
            MaxIterations -> 10000]



            {19762., {x -> 19762, y -> 7311}}




            And with your definition of constraint:



            constraint /. maxX[[2]]



            True








            share|improve this answer














            share|improve this answer



            share|improve this answer








            edited yesterday

























            answered yesterday









            Henrik SchumacherHenrik Schumacher

            59.4k582165




            59.4k582165












            • $begingroup$
              But constraint /. x -> 19762 /. y -> 8647 results in False?
              $endgroup$
              – JimB
              yesterday










            • $begingroup$
              @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
              $endgroup$
              – Henrik Schumacher
              yesterday












            • $begingroup$
              @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
              $endgroup$
              – gaganso
              yesterday


















            • $begingroup$
              But constraint /. x -> 19762 /. y -> 8647 results in False?
              $endgroup$
              – JimB
              yesterday










            • $begingroup$
              @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
              $endgroup$
              – Henrik Schumacher
              yesterday












            • $begingroup$
              @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
              $endgroup$
              – gaganso
              yesterday
















            $begingroup$
            But constraint /. x -> 19762 /. y -> 8647 results in False?
            $endgroup$
            – JimB
            yesterday




            $begingroup$
            But constraint /. x -> 19762 /. y -> 8647 results in False?
            $endgroup$
            – JimB
            yesterday












            $begingroup$
            @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
            $endgroup$
            – Henrik Schumacher
            yesterday






            $begingroup$
            @JimB D'oh. Yeah, I did the simplification wrong. -.- Thanks for pointing that out.
            $endgroup$
            – Henrik Schumacher
            yesterday














            $begingroup$
            @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
            $endgroup$
            – gaganso
            yesterday




            $begingroup$
            @HenrikSchumacher, thank you for this. This works for x but when I try to find the maximum y similarly, I still get the same message - NMaximize[{y, res}, {x, y}, Integers, MaxIterations -> 100000]. Output: NMaximize::cvdiv: Failed to converge to a solution. The function may be unbounded.
            $endgroup$
            – gaganso
            yesterday


















            draft saved

            draft discarded




















































            Thanks for contributing an answer to Mathematica 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.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathematica.stackexchange.com%2fquestions%2f194684%2fnmaximize-is-not-converging-to-a-solution%23new-answer', 'question_page');
            }
            );

            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







            Popular posts from this blog

            GameSpot

            connect to host localhost port 22: Connection refused

            Getting a Wifi WPA2 wifi connection