Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

Solution 63316

Submitted on 20 Mar 2012

Incorrect

121Size
Leading solution size is 76.
This solution is locked. To view this solution, you need to provide a solution of the same size or smaller.

Test Suite

Test
Code Input and Output
1
Fail
 
%%
% Rosenbrock's banana function
F=@(x) 100*(x(2)-x(1).^2).^2 + (1-x(1)).^2;
gradF=@(x) [100*(4*x(1).^3-4*x(1).*x(2))+2*x(1)-2; 100*(2*x(2)-2*x(1).^2)];
x0 = [-1.9; 2.0];
x1=[
   -1.4478
    2.1184];
x2=[
    1.7064
    2.9446];
f1=6.0419;
f2=0.6068;
[xmin,fmin]=SteepestDescent(F,gradF,x0,0.01,1)
assert(norm(xmin-x1)<0.2||norm(xmin-x2)<0.2)
assert( abs(fmin-f1)<0.5|| abs(fmin-f2)<0.5) % 2 local min
Error: Assertion failed.
2
Fail
 
%%
% Rosenbrock's banana function
F=@(x) 100*(x(2)-x(1).^2).^2 + (1-x(1)).^2;
gradF=@(x) [100*(4*x(1).^3-4*x(1).*x(2))+2*x(1)-2; 100*(2*x(2)-2*x(1).^2)];
x0 = [0; 0];
xcorrect=[1;1];
fcorrect=0;
[xmin,fmin]=SteepestDescent(F,gradF,x0) % 20 iterations default
assert(norm((xmin-xcorrect),inf)<1)
assert(abs(fmin-fcorrect)<0.8);
Error: Assertion failed.
3
Fail
 
%%
% Rosenbrock's banana function
F=@(x) 100*(x(2)-x(1).^2).^2 + (1-x(1)).^2;
gradF=@(x) [100*(4*x(1).^3-4*x(1).*x(2))+2*x(1)-2; 100*(2*x(2)-2*x(1).^2)];
x0 = [1.1; 0.9];
xcorrect=[1;1];
fcorrect=0;
[xmin,fmin]=SteepestDescent(F,gradF,x0,1e-2,2000)
assert(isequal(round(xmin),xcorrect))
assert(isequal(round(fmin),fcorrect))
Error: Assertion failed.