Error Not enough input arguments when using nonlcon for Fmincon command
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I have just studied Matlab so i am so sorry if this problem is 'stupid'. I am stuck on dealing error 'Error Not enough input arguments' when i use nonlcon for Fmincon command. Here is my code:
%THE ROBUST RELIABILITY DESIGN METHOD
% Input data: mean value & standard deviation
mD0=1200; stdD0=6;
mD1=1000; stdD1=5;
mF=1.3*10^6; stdF=1.2*10^5;
mr=135; stdr=5.265;
% variable h
syms h
% mean value of limit state equation
mg = mr - 3*mF*(mD0-mD1)/(pi*mD1*h^(2))
% variance of limit state equation
varg = stdr^(2) + (3*(mD0-mD1)*stdF/(pi*mD1*h^(2)))^(2) +...
(3*mF*stdD0/(pi*mD1*h^(2)))^(2) + (3*mF*mD0*stdD1/(pi*mD1^(2)*h^(2)))^(2)
% Standard deviation of limit state equation
stdg=sqrt(varg)
vpa(stdg)
A1=1/stdg;
B=6*mF*(mD0-mD1)/(pi*mD1*h^3);
beta=mg/stdg;
f2 = matlabFunction(A1*B*(exp(-beta^2/2))/(2*pi)^(1/2));
%Using fmincon command to solve The Robust Reliability Design
A=-1; b=-50;
h0=50;
lb = [];
ub = [];
Aeq = [];
beq = [];
nonlcon=@constrain;
fmin = fmincon(f2,h0,A,b,Aeq,beq,lb,ub,nonlcon)
Here is constrain function:
%Constrain function
function [c, ceq] = constrain(h,mD0,stdD0,mD1,stdD1,mF,stdF,mr,stdr)
mg = mr - 3*mF*(mD0-mD1)/(pi*mD1*h^(2));
stdg= sqrt(stdr^(2) + (3*(mD0-mD1)*stdF/(pi*mD1*h^(2)))^(2) +...
(3*mF*stdD0/(pi*mD1*h^(2)))^(2) + (3*mF*mD0*stdD1/(pi*mD1^(2)*h^(2)))^(2));
c = (0.00336*stdg-mg);
ceq = [];
Please help me to solve this problem. Thanks all so much!
1 Comment
Matt J
on 5 Nov 2015
Incidentally, inequality constraints like
A=-1; b=-50;
are not a good way to express upper and lower bounds. You should express this as
lb=50;
Accepted Answer
Matt J
on 5 Nov 2015
Edited: Matt J
on 5 Nov 2015
nonlcon=@(h) constrain(h,mD0,stdD0,mD1,stdD1,mF,stdF,mr,stdr);
so that MATLAB knows that it is a function of h with Extra Parameters mD0,stdD0,mD1,stdD1,mF,stdF,mr, and stdr.
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