Unable to solve the collocation equations -- a singular Jacobian encountered

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MINATI PATRA 2020-10-15

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https://ww2.mathworks.cn/matlabcentral/answers/615048-unable-to-solve-the-collocation-equations-a-singular-jacobian-encountered

评论： MINATI PATRA 2020-10-23

b1 = 0.1; b2 = 0.01; A = 0.1; L = 1; b = 0.3; M = 1; R = 2; E = 1; Pr = 2; N = 2; rho = 1; a1 = 1; Ec = 10; G = 1;
BC = @(ya,yb)[ya(1)-R; ya([2;7])-1;  yb([1;2;7;9]); yb(5)+ yb(1); yb(6)-E;]; 
ODE = @(x,y) [y(2);  y(3);  exp(b1*y(7))*(-L*b*y(4)*(y(4)-y(2))+M*y(2)+y(2)^2-y(1)*y(3)+A*(y(2)+(x/2)*y(3)))+b1*y(8)*y(3);
    (b*(y(2)-y(4))-y(4)^2-A*y(4))/(y(5)+A.*(x/2));                   (b*(y(2)+y(5))-A*y(5))/(y(5)+A.*(x/2));  
    -(y(6)*(y(4)+(b*(y(2)+y(5))-A*y(5))/(y(5)+A.*(x/2))))/y(5);      y(8);   
    (2*y(2)*y(7)-y(1)*b2*y(8)+(A/2)*(4*y(7)+x*y(8))-(N/rho)*(a1*(y(9)-y(7))+b*Ec*(y(4)-y(1))^2))/(1+b2*y(7));
    (a1*G*(y(7)-y(9))-2*(A+y(4))*y(9)-(A.*x/2)*y(8))/y(5);];
xa = 0; xb = 6; x = linspace(xa,xb,100);solinit = bvpinit(x,[R 1 1 0 1 0 1 1 E]);
sol = bvp5c(ODE,BC,solinit);  S = deval(sol,x);
figure(2),plot(x,S(2,:),'Linewidth',1.5);xlabel('\bf\eta');ylabel('\bff^\prime(\eta)');hold on
%%  when I run this code ERROR comes