Optimisation of function containing matrix

I am having trouble optimising this system. I have been trying to use fmincon without success.
C is a 16x16 matrix, mo and v and 1 are 16x1 vectors. I want to choose mo to maximise x = c*mo+v
The constraints are: the components of mo must add to one (I think I've done this one)
and each component of x should be equal, that is x1=x2=...=x16 where x=c*mo+v (I have no idea how to represent this)
fun = @(mo) -C*mo-v;
A=[];
b=[];
Aeq= ones(1,16);
beq= 1;
lb = zeros(16,1);
ub = ones(16,1);
m0 = 1/16*ones(16,1);
mo = fmincon(fun,m0,A,b,Aeq,beq,lb,ub)
Please let me know where I'm going wrong...

3 Comments

Can you share C and v?
C =
Columns 1 through 10
1.0003 0.0245 0.0052 0.0172 0.0273 0.0220 0.0171 0.0208 0.0073 0.0218
0.0054 0.9994 0.0100 0.0326 0.0329 0.0369 0.0173 0.0155 0.0224 0.0269
0.0152 0.0097 1.0001 0.0173 0.0374 0.0220 0.0222 0.0208 0.0174 0.0219
0.0001 -0.0000 0.0000 1.0005 0.0255 0.0054 0.0103 0.0101 0.0007 0.0057
0.0001 -0.0000 0.0000 0.0056 1.0006 0.0103 0.0052 0.0050 0.0055 0.0204
0.0001 -0.0003 -0.0000 0.0059 0.0108 1.0007 0.0009 -0.0097 0.0156 0.0054
0.0001 -0.0001 -0.0000 0.0112 0.0110 0.0255 1.0005 0.0001 0.0359 0.0105
0.0001 -0.0001 -0.0000 0.0112 0.0110 -0.0041 0.0257 1.0004 0.0262 0.0156
0.0000 -0.0003 -0.0000 0.0205 0.0008 0.0005 0.0005 0.0002 1.0005 0.0003
0.0001 -0.0001 -0.0000 0.0157 0.0011 0.0105 0.0056 0.0053 0.0108 1.0004
0.0001 -0.0002 -0.0000 0.0111 0.0210 0.0157 0.0162 0.0152 0.0213 0.0009
0.0000 -0.0003 -0.0000 0.0107 0.0154 0.0007 0.0150 -0.0000 0.0155 0.0054
0.0050 -0.0104 -0.0001 0.0213 0.0212 0.0164 0.0456 0.0151 0.0169 0.0159
-0.0001 -0.0200 -0.0001 0.0095 -0.0004 0.0092 -0.0102 -0.0052 -0.0006 0.0047
0.0000 -0.0101 -0.0001 0.0102 0.0054 0.0151 0.0006 -0.0099 0.0002 0.0001
0.0100 -0.0000 0.0000 0.0158 0.0309 0.0058 0.0007 0.0005 0.0057 0.0158
Columns 11 through 16
0.0213 0.0179 0.0317 0.0165 0.0165 0.0064
0.0068 0.0479 0.0367 0.0270 0.0316 0.0213
0.0216 0.0228 0.0316 0.0167 0.0164 0.0163
0.0005 0.0055 0.0002 0.0003 0.0002 0.0155
0.0007 0.0007 0.0003 0.0003 0.0002 0.0203
0.0152 0.0307 0.0204 0.0109 0.0107 0.0002
0.0158 0.0264 0.0008 0.0110 0.0007 0.0104
0.0158 0.0212 0.0054 0.0009 0.0055 0.0106
0.0149 0.0205 0.0053 0.0203 0.0053 0.0002
0.0205 0.0060 0.0056 0.0005 0.0054 0.0152
1.0009 0.0214 0.0204 0.0010 0.0058 0.0006
0.0002 1.0008 0.0004 0.0153 0.0200 0.0005
0.0159 0.0169 1.0008 0.0257 0.0202 0.0009
-0.0150 0.0041 0.0043 0.9998 -0.0103 -0.0002
0.0002 0.0151 0.0199 0.0004 1.0003 -0.0000
0.0154 0.0108 0.0057 0.0104 0.0054 1.0008
v is a zero vector
It is better to attach data as mat file

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 Accepted Answer

While waiting for the data, I try to solve one of the questions. you can set the missing constraint as
x1-x2 = 0
x2-x3 = 0
...
so, let's call M the matrix with +1 -1 along the diagonal
M = diag(ones(16,1),0)+diag(-ones(15,1),1);
The last row has to be removed
% remove last row
M = M(1:end-1,:);
now, x = C*mo+v and we want M*x = 0, so Mx = M*C*mo+M*v = 0 and the new equality constraint is
% new constraints
Aeq2 = M*C;
beq2 = -M*v;
% append
Aeq = [Aeq; Aeq2];
beq = [beq; beq2];
However, the main problem is that your objective function returns a vector and not a scalar quantity. I don't know your problem but is the sum of all x a feasible objective function to maximize?
fun = @(mo) -sum(C*mo+v);
In this case the solution is
>> mo
mo =
0.0549
0.0481
0.0524
0.0668
0.0672
0.0644
0.0615
0.0627
0.0661
0.0655
0.0623
0.0653
0.0570
0.0737
0.0689
0.0633
>> sum(mo)
ans =
1
>> C*mo
ans =
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720
0.0720

4 Comments

Will this work though? The variable I am optimising is mo and x is a function of mo.
So the optimisation constraint is Aeq.mo=beq
So that would give mo(1)=...=mo(16) but i was x(1)=...=x(16) where x=C*mo+v
Sorry, I know my choice of variables makes this confusing
You are right, sorry for the misunderstanding. I edited the answer
Isabelle, is it what you want?
Yes, that's perfect. Thank you

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