Hi everyone i'm new to matlab can anyone help me to solve the equations listed in the image using matlab functions .whenever i'm trying to solving it is showing error and more ever can anyone tell is it correct way to solve these equations

[Star Strider]

Post the code not the screencap! We have better things to do that to type it in ourselves, and risk introducing other errors.

Also, what are you doing? If you’re having problems running your code or solving your equations and you entered them incorrectly in your code, we have absolutely no way of knowing without seeing the equations you started with.

And as Image Analyst states, MATLAB does double precision by default. Delete Line #2.

[Rajavardhan]

 I tried it by removing line #2 but also it is showing error as alpha dele and n are undefined variables and i'm actually using this code in matlab function block in simulink with V D and rho as input to get alpha dele and n as output

function[alpha,dele,n] = trimalgorithm(V,D,rho)

CD=0.08712-(0.05593*alpha)+(3.4825*alpha^2)+(0.2258*dele^2)+(0.1471*dele);

CL=0.1748+(2.453*alpha)-(1.691*alpha^2)+(29.986*alpha^3)-(49.245*alpha^4)-(0.3638*dele^2)+(0.7405*dele);

Jad=V/(n*D);

qdyn=0.5*rho*V^2;

I=4/(pi*pi)*rho^2*n^2*D^4;

T=I*(-0.0948*Jad^2+0.058*Jad+0.0761);

eqn1=-CD*qdyn*0.0618+T*cos(alpha)==0;

eqn2=-CL*qdyn*0.0618+T*sin(alpha)+2.943==0;

eqn3=0.0385-(0.59977*alpha)-(1.27402*alpha^2)-(0.1587*dele^2)-(0.4106*dele)==0;

[alpha,dele,n]=solve(eqn1,eqn2,eqn3,alpha,dele,n);

end

[Star Strider]

I didn’t pick up on its being a Simulink model. I added that to the product tags so someone proficient in Simulink will see it.

Answer 1

[Image Analyst]

Simply get rid of the line that says "double ....." That is not MATLAB syntax and you don't need to declare variables in advance. But you do need to define values for alpha, dele, and n.

[Rajavardhan]

actually i need to find the values of alpha dele and n by giving V D rho as input and more ever i'm using matlab function block to solve these everytime it is showing parse error