My system hangs on executing the code. i am using vpasolve() to calculate m15 and using that m15 again to another equation to plot.

syms beta15

eqn15 =cot(def15)== tan(beta15)*(((k+1)*m*m)/(2*(m*m*sin(beta15)^2-1))-1);

s15 = vpasolve(eqn15,beta15,1);

S15=abs(s15);

n15=2+(k-1)*(m*sin(S15))^2;

d15=(2*k*(m*sin(S15))^2-(k-1))*(sin(S15-def15))^2;

m15=(n15/d15)^0.5;

% % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % % %

% Pressure deflection diagram for theta=15

pr15=linspace(1,7.8,1000000);

msn15=(k2+pr15)/k1;

ct15=((k1*m15*m15-(k2+pr15))./(k2+pr15)).^0.5;

mcs15=(k1*m15*m15-2*(k2+pr15))/k1;

tn15=(2*ct15.*(msn15-1))./(k*m15*m15+2+mcs15);

theta15=atand(tn15);

a15=max(real(theta15));

A(3)= plot(theta15-15,pr15,'color',[0.8500 0.3250 0.0980],'LineWidth',1.1);

hold on

A(4)=plot(-theta15-15,pr15,'color',[0.8500 0.3250 0.0980],'LineWidth',1.1);

hold on

[Star Strider]

This appears to be similar to the problem presented in Solving for angle (Beta) using vpasolve although here several variables are either missing or undeclared.

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