quantize and increase variable in fminimax

my first question how can i increase vaariable in fminimax in below code when i add another variable only the one i put in function get value from x0 and another one remain empty

clear all
q=20;
random_numbersw = rand(1,20);            % Random number from 0 to 1
random_numberst = -90 + (90 + 90) * rand(1, 20);        % Random number from -90 to 90
x0 = [ random_numberst,random_numbersw ] ;     %Initiat delta
ub = zeros(1, 40);  % Initialize a matrix of zeros with 40 elements
ub(1:20) = 1;       % Set values from 1 to 21 to 0
ub(21:40) = 90;     % Set values from 22 to 40 to 90
lb = zeros(1, 40);  % Initialize a matrix of zeros with 40 elements
lb(1:20) = 0;       % Set values from 1 to 21 to 0
lb(21:40) = -90;    % Set values from 22 to 40 to 90
[x,fval] = fminimax(@costy,x0,[],[],[],[],lb,ub);
function y = costy(w,deltaTeta)
f=9*10^9; %Freq
j=sqrt(-1);     %Define Imaginary
l=(3*10^8)/f;   %Lambda
k=(2*pi)/l;     %Constant
d=0.5*l;        %Distant of each element
q=20;
teta1=((-4):0.1:(-2));
g = zeros(q,length(teta1));
    for h=1:q
    
      for aa = 1:length(teta1)
        
      g(h,aa) = g(h,aa)+(w(h) * ( exp(j*(h-1) * (k*d*sind(teta1(aa)+deltaTeta(h))))));      %w W
      end
    end
    y = abs(sum(g,1));
end

here first is w and second one is detaTeta

[Matt J]

The first line of costy says that a variablce called y is supposed to be returned. However, nothing called y appears anywhere in the code.

[koorosh dastan]

thanks

i edit that

[Lea]

You have set up your cost function as a function of two variables, but it should have one, see https://www.mathworks.com/help/optim/ug/passing-extra-parameters.html. Also, is your cost function guaranteed to be a real number? Note that you can't optimize a complex objective.

[koorosh dastan]

thx i change it to this

           g(h,aa) = g(h,aa)+(deltaTeta(h) * ( exp(j*(h-1) * (k*d*sind(teta1(aa)+deltaTeta(h+q))))));      %w W
      end

so i have only one input

but how can i quantize my deltateta that means

i like to change deltateta(1:20) whith step of 0.1 but from deltaTeta(21:40) it change with step of 5