Using For loop to plot graphs of functions (2024)

See also:

syms w e d n A Z F Q;

w = pi;

e = 0.5;

d = 10;

n = 1;

A_values = 0:0.5:10;

num_A_values = length(A_values);

sol = nan(num_A_values, 3); % Initialize with NaN to handle cases with no solution

for i = 1:num_A_values

A = A_values(i);

eqn1 = Z + A * w / (1 - Q * (1 + e)) * cos(F) == 0;

eqn2 = cos(F + 2 * Q * n * pi) + Z * ((e - Q * (1 + e)) / (A * w)) == 0;

eqn3 = A - 1 / (2 * w * abs(sin(Q * n * pi))) * (((1 - e) * Z)^2 + (d * w + 2 * (1 + e) * (1 - Q) * Q * n * pi * Z)^2)^0.5 == 0;

equations = [eqn1, eqn2, eqn3];

vars = [Z, F, Q];

range = [-40 40; 0 6; -1 1]; % Q is typically between -1 and 1 based on its typical physical range

% Solve the equations for the current value of A

try

temp = vpasolve(equations, vars, range);

% Handle the case where vpasolve might return multiple solutions or empty

if ~isempty(temp)

if isstruct(temp)

if isfield(temp, 'Z') && isfield(temp, 'F') && isfield(temp, 'Q')

sol(i, 1) = double(temp.Z);

sol(i, 2) = double(temp.F);

sol(i, 3) = double(temp.Q);

end

elseif iscell(temp) && ~isempty(temp{1})

temp = temp{1}; % Extract the first solution

if isfield(temp, 'Z') && isfield(temp, 'F') && isfield(temp, 'Q')

sol(i, 1) = double(temp.Z);

sol(i, 2) = double(temp.F);

sol(i, 3) = double(temp.Q);

end

end

end

catch

% Handle any unexpected errors by skipping to the next iteration

continue;

end

end

figure;

subplot(2, 2, 1)

plot(A_values, sol(:, 1), 'o-');

xlabel('A');

ylabel('Z');

title('Z vs A');

subplot(2, 2, 2)

plot(A_values, sol(:, 2), 'o-');

xlabel('A');

ylabel('F');

title('F vs A');

subplot(2, 2, 3)

plot(A_values, sol(:, 3), 'o-');

xlabel('A');

ylabel('Q');

title('Q vs A');

sgtitle('Solutions of the System of Equations');