Size of Q is undefined

function [j] = armijo_grad_direction_dnm_f1(P1,VG,sigma)
j = 0;
signal = 0;
nn = size(Q);
n = nn(1);
I = eye(n);
while( signal == 0 && j < MAX_j)
    Q = P1^(1/2)*expm(P1^(-1/2)*2^(-j)*VG*P1^(-1/2))*P1^(1/2); % Geodesic with direction 2^(-j)*VG starting at P1. 
    PHIQ  = 1/2*trace(I-2*Q^(-1)+(Q^(-1))^(2)); % Merit Function at Q.
    PHIP1  = 1/2*trace(I-2*P1^(-1)+(P1^(-1))^(2));
    ARM = PHIQ - PHIP1 - 2^(-j)*sigma*trace(VG*P1^(-1)*VG*P^(-1)); %Armijo Gradient Direction
    if(ARM > 0)
        j = j+ 1;
    else
        signal = 1;
    end  
end

if ( j >= MAX_j)
    fprintf('\nArmijo:  j not found with %d iterations.\n',MAX_j);
    return;
end
end

[KSSV]

How did you run the function? What inputs you have used?

[feeroz babu]

I am running this in octave then I got

error: 'P1' undefined near line 4, column 4

error: called from

armijo_newton_direction_dnm_f1 at line 4 column 4

Answer 1

[KSSV]

You need to define the input variables and then call the function. It seems you are striaght away hitting the f5/ run button so you are getting error.

P1 =   define your value ;   % enter value 
VG = define your value ;   % enter input 
sigma = define your value ; 
% now call the function 
j = armijo_grad_direction_dnm_f1(P1,VG,sigma)

[feeroz babu]

Thank you very much.

Actually, in this code there is 'n'. So, we have to fix the value of 'n' ?

[feeroz babu]

P1 = [2, 0, 1; 0, 3, 1;1,1,4];

>> VN = [2,0,1;0,3,1;1,1,4];

>> sigma = 1/4;

>> a=1/2;

>> b=1/3;

>> MAX_j=10;

>> j = armijo_newton_direction_dnm_f2(P1,VN,sigma,a,b,MAX_j)

error: invalid call to script /home/firoz/Documents/D/Dropbox/Manifold/Manopt_7.0/MATLAB_codes/codigo_publico/Size/size.m

error: called from

size

armijo_newton_direction_dnm_f2 at line 4 column 4

[KSSV]

Save the function in the current working directory and call.

[feeroz babu]

I did but I got

size

armijo_grad_direction_dnm_f1 at line 4 column 4 (nn = size(P1);)

[Walter Roberson]

Your /home/firoz/Documents/D/Dropbox/Manifold/Manopt_7.0/MATLAB_codes/codigo_publico/Size/size.m is very very likely to interfere with the regular MATLAB size() function.

[KSSV]

Your function name is _armijo_grad_direction_dnm_f1 and you are trying to call armijo_newton_direction_dnm_f2 it seems,

[feeroz babu]

Yes I have two functions. Ok, done. I selected wrong directory. Thank you for your kind help. My code runs.