Error using fmincon, the function cannot continue

2021 6 15
2 个回答
回答已采纳
更新时间：2021 6 21
8 次查看（30 天）

0 个投票

Hi, everyone.
I'm trying to optimize a function with 8 optimization variables. I set up initial point and costraints but appears the following error:
"Error using optim.problemdef.OptimizationProblem/solve
Objective function is undefined at initial point. Fmincon cannot continue.
Error in curvatura_V7 (line 75)
[sol,fval,exitflag,output] = solve(prob,x0);"
the code is as follow:
aymax = 5;
V = 70;
deltay = 60;
deltax = 3;
intorno = sqrt(deltax^2+deltay^2);
dmin = 3;
type objfun
rof1 = optimvar('rof1');
rof2 = optimvar('rof2');
rof3 = optimvar('rof3');
rof4 = optimvar('rof4');
sf1 = optimvar('sf1');
sf2 = optimvar('sf2');
sf3 = optimvar('sf3');
sf4 = optimvar('sf4');
obj = fcn2optimexpr(@objfun,rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4);
prob = optimproblem('Objective',obj);
constr1 = (-aymax / (V/3.6)^2) <= rof1;
prob.Constraints.curvatura1 = constr1;
constr2 = (aymax / (V/3.6)^2) >= rof1;
prob.Constraints.curvatura1 = constr2;
constr3 = (-aymax / (V/3.6)^2) <= rof2;
prob.Constraints.curvatura2 = constr3;
constr4 = (aymax / (V/3.6)^2) >= rof2;
prob.Constraints.curvatura2 = constr4;
constr5 = (-aymax / (V/3.6)^2) <= rof3;
prob.Constraints.curvatura3 = constr5;
constr6 = (aymax / (V/3.6)^2) >= rof3;
prob.Constraints.curvatura3 = constr6;
constr7 = (-aymax / (V/3.6)^2) <= rof4;
prob.Constraints.curvatura4 = constr7;
constr8 = (aymax / (V/3.6)^2) >= rof4;
prob.Constraints.curvatura4 = constr8;
constr9 = sf1 >= 0 ;
prob.Constraints.ascissa1 = constr9;
constr10 = sf1 <= sf2;
prob.Constraints.ascissa1 = constr10;
constr11 = sf2 >= sf1;
prob.Constraints.ascissa2 = constr11;
constr12 = sf2 <= sf3;
prob.Constraints.ascissa2 = constr12;
constr13 = sf3 >= sf1+sf2;
prob.Constraints.ascissa3 = constr13;
constr14 = sf3 <= sf4;
prob.Constraints.ascissa3 = constr14;
constr15 = sf4 >= sf1+sf2+sf3;
prob.Constraints.ascissa4 = constr15;
constr16 = sf4 <= 2*intorno;
prob.Constraints.ascissa4 = constr16;
show(prob)
x0.rof1 = 0;
x0.rof2 = 0;
x0.rof3 = 0;
x0.rof4 = 0;
x0.sf1 = 0;
x0.sf2 = 0;
x0.sf3 = 0;
x0.sf4 = 0;
[sol,fval,exitflag,output] = solve(prob,x0);

请先登录，再回答此问题。

 采纳的回答

Walter Roberson
Walter Roberson 2021-6-19
Ran in:

0 个投票

Ran in:
aymax = 5;
V = 70;
deltay = 60;
deltax = 3;
intorno = sqrt(deltax^2+deltay^2);
dmin = 3;
rof1 = optimvar('rof1');
rof2 = optimvar('rof2');
rof3 = optimvar('rof3');
rof4 = optimvar('rof4');
sf1 = optimvar('sf1');
sf2 = optimvar('sf2');
sf3 = optimvar('sf3');
sf4 = optimvar('sf4');
obj = fcn2optimexpr(@objfun,rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4);
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
prob = optimproblem('Objective',obj);
constr1 = (-aymax / (V/3.6)^2) <= rof1;
prob.Constraints.curvatura1 = constr1;
constr2 = (aymax / (V/3.6)^2) >= rof1;
prob.Constraints.curvatura1 = constr2;
constr3 = (-aymax / (V/3.6)^2) <= rof2;
prob.Constraints.curvatura2 = constr3;
constr4 = (aymax / (V/3.6)^2) >= rof2;
prob.Constraints.curvatura2 = constr4;
constr5 = (-aymax / (V/3.6)^2) <= rof3;
prob.Constraints.curvatura3 = constr5;
constr6 = (aymax / (V/3.6)^2) >= rof3;
prob.Constraints.curvatura3 = constr6;
constr7 = (-aymax / (V/3.6)^2) <= rof4;
prob.Constraints.curvatura4 = constr7;
constr8 = (aymax / (V/3.6)^2) >= rof4;
prob.Constraints.curvatura4 = constr8;
constr9 = sf1 >= 0 ;
prob.Constraints.ascissa1 = constr9;
constr10 = sf1 <= sf2;
prob.Constraints.ascissa1 = constr10;
constr11 = sf2 >= sf1;
prob.Constraints.ascissa2 = constr11;
constr12 = sf2 <= sf3;
prob.Constraints.ascissa2 = constr12;
constr13 = sf3 >= sf1+sf2;
prob.Constraints.ascissa3 = constr13;
constr14 = sf3 <= sf4;
prob.Constraints.ascissa3 = constr14;
constr15 = sf4 >= sf1+sf2+sf3;
prob.Constraints.ascissa4 = constr15;
constr16 = sf4 <= 2*intorno;
prob.Constraints.ascissa4 = constr16;
show(prob)
OptimizationProblem : Solve for: rof1, rof2, rof3, rof4, sf1, sf2, sf3, sf4 minimize : objfun(rof1, rof2, rof3, rof4, sf1, sf2, sf3, sf4) subject to curvatura1: 0.013224 >= rof1 subject to curvatura2: 0.013224 >= rof2 subject to curvatura3: 0.013224 >= rof3 subject to curvatura4: 0.013224 >= rof4 subject to ascissa1: sf1 - sf2 <= 0 subject to ascissa2: sf2 - sf3 <= 0 subject to ascissa3: sf3 - sf4 <= 0 subject to ascissa4: sf4 <= 120.1499
x0.rof1 = 0;
x0.rof2 = 0;
x0.rof3 = 0;
x0.rof4 = 0;
x0.sf1 = 0;
x0.sf2 = 0;
x0.sf3 = 0;
x0.sf4 = 0;
%[sol,fval,exitflag,output] = solve(prob,x0);
result = objfun(x0.rof1, x0.rof2, x0.rof3, x0.rof4, x0.sf1, x0.sf2, x0.sf3, x0.sf4)
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
Warning: Inf or NaN value encountered.
result = NaN
function erroredistanza = objfun(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4)
deltay = 60;
deltax = 3;
tau0 = 90;
tau0 = deg2rad(tau0);
dmin = 3;
roi1=0;
si1=0;
PSI1 = @(roi1,rof1,si1,sf1,s) tau0 + ((rof1*si1-roi1*sf1)/(si1-sf1))*s + ((roi1-rof1)/(si1-sf1))*(s.^2)/2;
PSI2 = @(rof1,rof2,sf1,sf2,s) ((rof2*sf1-rof1*sf2)/(sf1-sf2))*s + ((rof1-rof2)/(sf1-sf2))*(s.^2)/2;
PSI3 = @(rof2,rof3,sf2,sf3,s) ((rof3*sf2-rof2*sf3)/(sf2-sf3))*s + ((rof2-rof3)/(sf2-sf3))*(s.^2)/2;
PSI4 = @(rof3,rof4,sf3,sf4,s) ((rof4*sf3-rof3*sf4)/(sf3-sf4))*s + ((rof3-rof4)/(sf3-sf4))*(s.^2)/2;
funx1 = @(roi1,rof1,si1,sf1,s) integral(@(s) cos(PSI1(roi1,rof1,si1,sf1,s)),0,sf1);
funx2 = @(rof1,rof2,sf1,sf2,s) integral(@(s) cos(PSI2(rof1,rof2,sf1,sf2,s)),sf1,sf2);
funx3 = @(rof2,rof3,sf2,sf3,s) integral(@(s) cos(PSI3(rof2,rof3,sf2,sf3,s)),sf2,sf3);
funx4 = @(rof3,rof4,sf3,sf4,s) integral(@(s) cos(PSI4(rof3,rof4,sf3,sf4,s)),sf3,sf4);
funy1 = @(roi1,rof1,si1,sf1,s) integral(@(s) sin(PSI1(roi1,rof1,si1,sf1,s)),0,sf1);
funy2 = @(rof1,rof2,sf1,sf2,s) integral(@(s) sin(PSI2(rof1,rof2,sf1,sf2,s)),sf1,sf2);
funy3 = @(rof2,rof3,sf2,sf3,s) integral(@(s) sin(PSI3(rof2,rof3,sf2,sf3,s)),sf2,sf3);
funy4 = @(rof3,rof4,sf3,sf4,s) integral(@(s) sin(PSI4(rof3,rof4,sf3,sf4,s)),sf3,sf4);
funx = @(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funx1(roi1,rof1,si1,sf1) + funx2(rof1,rof2,sf1,sf2) + funx3(rof2,rof3,sf2,sf3) + funx4(rof3,rof4,sf3,sf4);
funy = @(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funy1(roi1,rof1,si1,sf1) + funy2(rof1,rof2,sf1,sf2) + funy3(rof2,rof3,sf2,sf3) + funy4(rof3,rof4,sf3,sf4);
fun2x =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funx(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - deltax;
fun2y =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funy(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - deltay;
fun3x =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) fun2x(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4).^2;
fun3y =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) fun2y(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4).^2;
d =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) sqrt(fun3x(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) + fun3y(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4));
erroredistanza = d(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - dmin;
end
... Look at the code. You divide by (si1-sf1) and (sf1-sf2) and (sf2-sf3) and (sf3-sf4) . si1 is 0, and sf1 to sf4 are passed in. Your initial values for all of the variables is 0, so you are dividing by (0-0) in multiple places.
If you divide by something in your objective, it is your responsibility to ensure that your constraints exclude the possibility that you are going to be dividing by 0, and that your initial point is not going to trigger a division by 0.

更多回答（1 个）

Tarunbir Gambhir
Tarunbir Gambhir 2021-6-18

1 个投票

The error message says the objective function is not defined at initial point. This means objfun(xo) returns a 'NaN' or errors out (where "objfun" is objective function and "xo" is the initial point). It could be that the initial point does not satisfy all the provided constraints for the objective function. Since you did not provide the 'objfun', I would not be able to help any further.
Anyway, to avoid this error you can simply try choosing a better initial point.

1 个评论
显示 -1更早的评论 隐藏 -1更早的评论

Andrea Mazzetto
Andrea Mazzetto 2021-6-19
this is my objfun
function erroredistanza = objfun(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4)
deltay = 60;
deltax = 3;
tau0 = 90;
tau0 = deg2rad(tau0);
dmin = 3;
roi1=0;
si1=0;
PSI1 = @(roi1,rof1,si1,sf1,s) tau0 + ((rof1*si1-roi1*sf1)/(si1-sf1))*s + ((roi1-rof1)/(si1-sf1))*(s.^2)/2;
PSI2 = @(rof1,rof2,sf1,sf2,s) ((rof2*sf1-rof1*sf2)/(sf1-sf2))*s + ((rof1-rof2)/(sf1-sf2))*(s.^2)/2;
PSI3 = @(rof2,rof3,sf2,sf3,s) ((rof3*sf2-rof2*sf3)/(sf2-sf3))*s + ((rof2-rof3)/(sf2-sf3))*(s.^2)/2;
PSI4 = @(rof3,rof4,sf3,sf4,s) ((rof4*sf3-rof3*sf4)/(sf3-sf4))*s + ((rof3-rof4)/(sf3-sf4))*(s.^2)/2;
funx1 = @(roi1,rof1,si1,sf1,s) integral(@(s) cos(PSI1(roi1,rof1,si1,sf1,s)),0,sf1);
funx2 = @(rof1,rof2,sf1,sf2,s) integral(@(s) cos(PSI2(rof1,rof2,sf1,sf2,s)),sf1,sf2);
funx3 = @(rof2,rof3,sf2,sf3,s) integral(@(s) cos(PSI3(rof2,rof3,sf2,sf3,s)),sf2,sf3);
funx4 = @(rof3,rof4,sf3,sf4,s) integral(@(s) cos(PSI4(rof3,rof4,sf3,sf4,s)),sf3,sf4);
funy1 = @(roi1,rof1,si1,sf1,s) integral(@(s) sin(PSI1(roi1,rof1,si1,sf1,s)),0,sf1);
funy2 = @(rof1,rof2,sf1,sf2,s) integral(@(s) sin(PSI2(rof1,rof2,sf1,sf2,s)),sf1,sf2);
funy3 = @(rof2,rof3,sf2,sf3,s) integral(@(s) sin(PSI3(rof2,rof3,sf2,sf3,s)),sf2,sf3);
funy4 = @(rof3,rof4,sf3,sf4,s) integral(@(s) sin(PSI4(rof3,rof4,sf3,sf4,s)),sf3,sf4);
funx = @(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funx1(roi1,rof1,si1,sf1) + funx2(rof1,rof2,sf1,sf2) + funx3(rof2,rof3,sf2,sf3) + funx4(rof3,rof4,sf3,sf4);
funy = @(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funy1(roi1,rof1,si1,sf1) + funy2(rof1,rof2,sf1,sf2) + funy3(rof2,rof3,sf2,sf3) + funy4(rof3,rof4,sf3,sf4);
fun2x =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funx(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - deltax;
fun2y =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) funy(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - deltay;
fun3x =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) fun2x(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4).^2;
fun3y =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) fun2y(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4).^2;
d =@(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) sqrt(fun3x(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) + fun3y(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4));
erroredistanza = d(rof1,rof2,rof3,rof4,sf1,sf2,sf3,sf4) - dmin;

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Numerical Integration and Differentiation 的更多信息

产品

版本

R2020b

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by