Error using fmincon and integral: taking integral variable as an array while performing computation

I am minimizing q for whole range of p from 2 to 20, to find the value of d, r_g,G_g. q is function of p,d, r_g, G_g.

But while computation p is behaving as an array values varing from 2 to 20. Because of this I am getting error. How to correct this. Here my part of code

[q] = optimizeParameters();% Call optimizeParameters to define the objective function q
options = optimset('PlotFcns', @optimplotfval);% Set optimization options

d0 = [-0.5, 24, 3e6];
lb = [-1, 24, 2e6];
ub = [0, 32, 6e6];
[solution,fval] = fmincon(@(x)integral(@(p)q(p,x(1),x(2),x(3)),2*pi,20*pi),d0,[],[],[],[],lb,ub,[],options); % minimize q for full range of p

function q = optimizeParameters()
   
    % syms p d r_g G_g 
    %p = 2*pi;
    theta = pi/4;
    Vs = 250;
    k = @(p)p/Vs;
    c = Vs/sin(theta);
    w5 = 0.001;
    n = 3;
    dl = -6;
    d1 = @(d)dl + 2 * n * d - d;

    q = @(p, d, r_g, G_g) calculateObjective(theta, p, d, r_g, G_g, Vs, k, c, w5, n, dl, d1);
end


function answer = calculateObjective(theta, p, d, r_g, G_g, Vs, k, c, w5, n, dl, d1);
    p % printing the p here which is giving an array because of this error in further computation
    
    % rest of the code

end

Answer 1

[Torsten]

[q] = optimizeParameters();% Call optimizeParameters to define the objective function q
options = optimset('PlotFcns', @optimplotfval);% Set optimization options
d0 = [-0.5, 24, 3e6];
lb = [-1, 24, 2e6];
ub = [0, 32, 6e6];
[solution,fval] = fmincon(@(x)integral(@(p)q(p,x(1),x(2),x(3)),2*pi,20*pi,'ArrayValued',true),d0,[],[],[],[],lb,ub,[],options); % minimize q for full range of p
function q = optimizeParameters()
   
    % syms p d r_g G_g 
    %p = 2*pi;
    theta = pi/4;
    Vs = 250;
    k = @(p)p/Vs;
    c = Vs/sin(theta);
    w5 = 0.001;
    n = 3;
    dl = -6;
    d1 = @(d)dl + 2 * n * d - d;
    q = @(p, d, r_g, G_g) calculateObjective(theta, p, d, r_g, G_g, Vs, k(p), c, w5, n, dl, d1(d));
end
function answer = calculateObjective(theta, p, d, r_g, G_g, Vs, k, c, w5, n, dl, d1);
    p % printing the p here which is giving an array because of this error in further computation
    
    % rest of the code
end