MATLAB: Contour Plot Problem…X-axis is defined by equation.

aerodynamicscontour

I want to generate a theta(x), beta(y), mach chart using the equation tan(theta)=2*cot(Beta)*[((M^2)*sin^2(Beta-1)) / ((M^2)*(1.4+cos(2*Beta))+2)].
theta should end up 0->~46 degrees. I want Mach numbers of 1.05->20. Beta = 0->90 degrees.
This is what I have (I know its' bad)…
beta=(1.05:.1:20); M=(1.05:.1:20); [B,M]=meshgrid(beta,M); theta=atand((2.*cot(beta)).*(((M.^2).*(sind(beta-1).^2))./((M.^2).*(1.4+cosd(2.*beta))+2))); contour(theta,B,M)

Best Answer

  • Two things...
    1) You need to replace beta with B in your theta definition, or you'll encounter matrix dimension clashes
    2) I assume you want cotd instead of cot for cotangent, since everything's in degrees.