求解超越方程。

function a =myfun(Tw2,I2,P2)

Tm=1.5;

Te=0.5;

T0=0.05;

Jw2=pi./10;

a(1)=(Jw2+atan((2*pi*Tm)./Tw2)+atan((2*pi*Te)./Tw2)+(2*pi*T0)./Tw2)-pi;

a(2)=atan(Tw2./(2*pi*I2))-Jw2;

a(3)=((100./P2)*sqrt(1+(tan(Jw2))^2)*1./sqrt(1+(Tm*2*pi./Tw2)^2)*1./sqrt(1+(0.5*2*pi./Tw2)^2))-1;

end

/*******************************

********************************/

clear

Jw22=fsolve('myfun',[2,2,3]);

不知为什么出现错误？

Subscripted assignment dimension mismatch.

Error in myfun (line 6)

a(1)=(Jw2+atan((2*pi*Tm)./Tw2)+atan((2*pi*Te)./Tw2)+(2*pi*T0)./Tw2)-pi;

Error in fsolve (line 218)

fuser = feval(funfcn{3},x,varargin{:});

Error in Test (line 2)

Jw22=fsolve('myfun',[2,2,3]);

Caused by:

Failure in initial user-supplied objective function evaluation. FSOLVE cannot continue.

Answer 1

[givesij]

哪是未知数呀?是这样吗？

function a=myfun(x)
%x(1)=Tw2,x(2)=I2,x(3)=P2
Tm=1.5;
Te=0.5;
T0=0.05;
Jw2=pi/10;
a(1)=(Jw2+atan((2*pi*Tm)./x(1))+atan((2*pi*Te)./x(1))+(2*pi*T0)./x(1))-pi;
a(2)=atan(x(1)./(2*pi*x(2)))-Jw2;
a(3)=((100./x(3))*sqrt(1+(tan(Jw2))^2)*1./sqrt(1+(Tm*2*pi./x(1))^2)*1./sqrt(1+(0.5*2*pi./x(1))^2))-1;
end

Jw22=fsolve('myfun',[2,2,3])

Jw22 =    1.3477    0.6601    5.8678