contour plot required for this code

K = 0.5; M = 0.5; p1 = 0.01; p2 = 0.01; p3 = 0.0; Pr = 2; Ec = 0.05; Q = 0.05; D = 10; b = 0.05; Bi = 0.15; 
p2v = linspace(0,0.2,101);Mv = [1 3 5];   
for k = 1:numel(Mv)
      M = Mv(k);
 for i = 1:length(p2v)
     p2 = p2v(i);
Cpf = 4179;rhof = 997;kf = 0.613;sgf = 5.5*10^(-5); Cps1 = 765;rhos1 = 3970;ks1 = 40;sis1 = 10^(-10); Cps2 = 5315;rhos2 = 6320;ks2 = 76.5;sis2 = 2.7*10^(-8);  Cps3 = 686.2;rhos3 = 4250;ks3 = 8.9538;sis3 = 6.27*10^(-5);H1 = ((1-p1)*(1-p2)*(1-p3))^-2.5;  H2 = (1-p3)*( (1-p2)*( 1-p1 + p1*rhos1/rhof ) + p2*rhos2/rhof ) + p3*rhos3/rhof; H3 = (1-p3)*( (1-p2)*(1-p1 + p1*rhos1*Cps1/(rhof*Cpf)) + p2*rhos2*Cps2/(rhof*Cpf) ) + p3*rhos3*Cps3/(rhof*Cpf);C2 = ( (sis1+2*sgf-2*p1*(sgf-sis1))/(sis1+2*sgf+p1*(sgf-sis1))); C3 = ( (sis2+2*C2-2*p2*(C2-sis2))/(sis2+2*C2+p2*(C2-sis2)) );A3 = ( (sis3+2*C3-2*p3*(C3-sis3))/(sis3+2*C3+p3*(C3-sis3)) ); B1 = ( (ks1+2*kf-2*p1*(kf-ks1))/(ks1+2*kf+p1*(kf-ks1)) ); B2 = ( (ks2+2*B1-2*p2*(B1-ks2))/(ks2+2*B1+p2*(B1-ks2)) ); H4 = ( (ks3+2*B2-2*p3*(B2-ks3))/(ks3+2*B2+p3*(B2-ks3)) ); 
ODE = @(x,y)[y(2);  y(3);  y(4); M*(x+K).^2*(A3/H1).*(y(2) + (x+K).*y(3)) - 2*y(4)./(x+K) + y(3)./(x+K).^2 - y(2)./(x+K).^3 - (H2/H1)*K*((x+K).^2.*(y(1)*y(4) - y(2)*y(3))) - y(1)*y(2) + (x+K).*(y(1)*y(3)-y(2)^2); y(6); - (Pr/H4)*( Q*(y(5) + exp(-D*x)) + H3*K*y(1)*y(6) + M*Ec*A3*y(2)^2 ) - y(6) ]; BC = @(ya,yb)[ya(1); ya(2)-1-b*(ya(3)-ya(2)/K); ya(6)-Bi*(ya(5)-1);  yb([2;3;5])];  xa = 0; xb = 6; x = linspace(xa,xb,101); solinit = bvpinit(x,[0 1 0 1 0 1]); sol = bvp5c(ODE,BC,solinit);  S = deval(sol,x); 

[X,Y] = meshgrid(p2,S(1,:)); psi(i,:) = X.*Y;
 end
end
figure(42),contourf(X,Y,psi,50,'ko','ShowText','on','LineWidth',1.5),hold on;ax = gca; ax.XColor = 'blue'; ax.YColor = 'blue'; ax.XAxis.FontSize = 12; ax.YAxis.FontSize = 12; ax.FontWeight = 'bold';

Error using contourf (line 57)
Vector X must be strictly increasing or strictly decreasing with no repeated values.

xlabel('\bfp2','color','blue','FontSize', 14); ylabel('\bf\psi','color','blue','FontSize', 14); % colormap hot
%% I need contourf plot for  'p2'  versuses 'psi' for different values of     M = [1 3 5];

Answer 1

[Ishu]

Hi Minati,

When plotting contour plots, the inputs "X" and "Y" must be strictly increasing or decreasing if they are specified as vectors. This requirement does not apply when "X" and "Y" are matrices.

As your "X" and "Y" inputs are vectors and their values are not strictly increasing or decreasing, you should sort these vectors to resolve the error.

XSorted = sort(unique(X));
YSorted = sort(unique(Y));

Another way is you can use "meshgrid" to convert your vectors into matrices.

[X_Matrix, Y_matirx] = meshgrid(X,Y);

[MINATI PATRA]

Dear Ishu

Neither of them worked.

[MINATI PATRA]

Any idea please