function dydt= project(t,psi)M=5; m=0.5; R=0.5; tau=10*sin(100*t); F=10*cos(10*t) ; ddx=2;dydt(1)=y(3);dydt(2)=y(4);dydt(3)=-(M*R^2*y(3) - 2*tau + 2*R^2*y(3)*m + 2*R*ddx*sin(y(1)))/(2*R*cos(y(1)))dydt(4)=(M^2*R^2*y(3) + 3*M*R^2*y(3)*m + 2*ddx*sin(y(1))*M*R - 2*tau*M + 2*cos(y(1))*sin(y(1))*R^2*y(3)^2 + 2*R^2*y(3)*m^2 + 2*ddx*sin(y(1))*R*m + 2*F*cos(y(1))*R - 2*tau*m)/(2*R^2*cos(y(1))^2)dydt=dydt';endMATLAB: Why the error is written here (Not enough input arguments.)
#ode45 not enough input arguments.
Related Solutions
Hi
The problem is not in solving
x = 0:0.8:pi;A = sin(x).^(1/3)B = cos(x).^(1/3)the operator
.^solves for either real or complex.
The problem lays in the fact that surf doesn't take in complex values.
To solve the long expression of H, since you are dealing with complex numbers, you have to plot 2 surfs, not one: Real and Imaginary, or Modulus and Phase
clctheta5=[0:0.1:pi];theta4=[0:0.1:pi];[X,Y]=meshgrid(theta4,theta5);H=(((((cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).*(cos(X).^2.*cos(Y).^2-cos(X).^2*sin(X).^2+cos(Y).^2.*sin(X).^2+cos(X).^2.*cos(Y).^4.*sin(X).^2+2*cos(X).^2.*sin(X).^2.*sin(Y).^2-cos(Y).^2.*sin(X).^2.*sin(Y).^2-cos(X).^2.*sin(X).^2.*sin(Y).^4))./6+(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^3./27+(cos(X).^2.*cos(Y).^2.*sin(X).^2)./2-(cos(X).^2.*cos(Y).^6.*sin(X).^2)./2-(cos(X).^2.*cos(Y).^2.*sin(X).^2.*sin(Y).^2)./2-cos(X).^2.*cos(Y).^4.*sin(X).^2.*sin(Y).^2).^2-((cos(X).^2.*cos(Y).^2)./3-(cos(X).^2.*sin(X).^2)./3+(cos(Y).^2.*sin(X).^2)./3+(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(X).^2+sin(X).^2.*sin(Y).^2).^2./9+(cos(X).^2*cos(Y).^4.*sin(X).^2)./3+(2.*cos(X).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(Y).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(X).^2.*sin(X).^2.*sin(Y).^4)./3).^3).^(1/2)-((cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).*(cos(X).^2.*cos(Y).^2-cos(X).^2.*sin(X).^2+cos(Y).^2.*sin(X).^2+cos(X).^2.*cos(Y).^4.*sin(X).^2+2.*cos(X).^2.*sin(X).^2.*sin(Y).^2-cos(Y).^2.*sin(X).^2.*sin(Y).^2-cos(X).^2.*sin(X).^2.*sin(Y).^4))./6-(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^3./27-(cos(X).^2.*cos(Y).^2.*sin(X).^2)./2+(cos(X).^2.*cos(Y).^6.*sin(X).^2)./2+(cos(X).^2.*cos(Y).^2.*sin(X).^2.*sin(Y).^2)./2+cos(X).^2.*cos(Y).^4.*sin(X).^2.*sin(Y).^2).^(1/3)+cos(X).^2./3-cos(Y).^2./3+sin(X).^2./3+((cos(X).^2.*cos(Y).^2)./3-(cos(X).^2.*sin(X).^2)./3+(cos(Y).^2.*sin(X).^2)./3+(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^2./9+(cos(X).^2.*cos(Y).^4.*sin(X).^2)./3+(2*cos(X).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(Y).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(X).^2.*sin(X).^2.*sin(Y).^4)./3)./(((((cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).*(cos(X).^2.*cos(Y).^2-cos(X).^2.*sin(X).^2+cos(Y).^2.*sin(X).^2+cos(X).^2.*cos(Y).^4.*sin(X).^2+2.*cos(X).^2.*sin(X).^2.*sin(Y).^2-cos(Y).^2.*sin(X).^2.*sin(X).^2-cos(X).^2.*sin(X).^2.*sin(Y).^4))./6+(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^3./27+(cos(X).^2.*cos(Y).^2.*sin(X).^2)./2-(cos(X).^2.*cos(Y).^6.*sin(X).^2)./2-(cos(X).^2.*cos(Y).^2.*sin(X).^2.*sin(Y).^2)./2-cos(X).^2.*cos(Y).^4.*sin(X).^2.*sin(Y).^2).^2-((cos(X).^2.*cos(Y).^2)./3-(cos(X).^2.*sin(X).^2)./3+(cos(Y).^2.*sin(X).^2)./3+(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^2./9+(cos(X).^2.*cos(Y).^4.*sin(X).^2)./3+(2.*cos(X).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(Y).^2.*sin(X).^2.*sin(Y).^2)./3-(cos(X).^2.*sin(X).^2.*sin(Y).^4)./3).^3).^(1/2)-((cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).*(cos(X).^2.*cos(Y).^2-cos(X).^2.*sin(X).^2+cos(Y).^2.*sin(X)^2+cos(X).^2.*cos(Y).^4.*sin(X).^2+2.*cos(X).^2.*sin(X).^2.*sin(Y).^2-cos(Y).^2.*sin(X).^2.*sin(Y).^2-cos(X).^2.*sin(X).^2.*sin(Y).^4))./6-(cos(Y).^2-cos(X).^2-sin(X).^2+cos(X).^2.*sin(Y).^2+sin(X).^2.*sin(Y).^2).^3./27-(cos(X).^2.*cos(Y).^2.*sin(X).^2)./2+(cos(X).^2.*cos(Y).^6.*sin(X).^2)./2+(cos(X).^2.*cos(Y).^2.*sin(X).^2.*sin(Y).^2)./2+cos(X).^2.*cos(Y).^4.*sin(X).^2.*sin(Y).^2).^(1/3)-(cos(X).^2.*sin(Y).^2)./3-(sin(X).^2.*sin(Y).^2)./3;figure(1);surf(X,Y,abs(H))figure(2);surf(X,Y,angle(H))
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John BG
syms theta1(t) theta2(t) theta3(t) m1=1; m2=1; m3=1; l1=1; l2=1; l3=1; g=9.81; tau1=1; tau2=1; tau3=1;e1= diff(theta1,2)*(l1^2*(m1+m2+m3)+l1)+... diff(theta1,2)*((m2+m3)*(l1*l2*cos(theta1-theta2)))+... diff(theta3,2)*(m3*l1*l3*cos(theta1-theta3))==... -(m2+m3)*(l1*l2*diff(theta2)^2*sin(theta1-theta2))-... m3*l1*l3*diff(theta3)^2*sin(theta1-theta3)-... (m1+m2+m3)*g*l1*cos(theta1)+tau1-tau2;e2= diff(theta1,2)*((m2+m3)*l1*l2*cos(theta1-theta2))+... diff(theta2,2)*(l2^2*(m2+m3)+l2)+... diff(theta3,2)*(m3*l2*l3*cos(theta2-theta3))==... (m2+m3)*l1*l2*diff(theta1)^2*sin(theta1-theta2)-... m3*l2*l3*diff(theta3)^2*sin(theta2-theta3)-... (m2+m3)*g*l2*cos(theta2)+tau2-tau3;e3= diff(theta1,2)*(m3*l1*l3*cos(theta1-theta3))+... diff(theta2,2)*(m3*l2*l3*cos(theta2-theta3))+... diff(theta3,2)*(l3^2*m3+l3)==... m3*l1*l3*diff(theta1)^2*sin(theta1-theta3)+... m3*l2*l3*diff(theta2)^2*sin(theta2-theta3)-... m3*g*l3*cos(theta3)+tau3;vars = [theta1(t); theta2(t); theta3(t)]V = odeToVectorField([e1,e2,e3])M = matlabFunction(V,'vars', {'t','Y'})interval = [0 20]; %time interval
y0 = [0; pi/2; 0; pi/2; 0; pi/2]; %initial conditions
ySol = ode45(M,interval,y0);tValues = linspace(interval(1),interval(2),1000);for i = 1:6 % denotes the number of solutions
yValues = deval(ySol,tValues,i); % i denotes the solution number
plot(tValues,yValues)hold onendPlot of 6 solutions:
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