solve differential equations use bvp4c

I use bvp4c to solve equations:

I use 5 points for xmesh, but get 7 points for x in the solution sol. How can I get the same number of points for x in the solution?

xmesh = linspace(0,pi/2,5);
solinit = bvpinit(xmesh, @guess);

sol = bvp4c(@bvpfcn, @bcfcn, solinit)

sol = struct with fields:
    solver: 'bvp4c'
         x: [0 0.1963 0.3927 0.7854 1.1781 1.3744 1.5708]
         y: [2x7 double]
        yp: [2x7 double]
     stats: [1x1 struct]

function dydx = bvpfcn(x,y) % equation to solve
dydx = zeros(2,1);
dydx = [y(2)
       -y(1)];
end
%--------------------------------
function res = bcfcn(ya,yb) % boundary conditions
res = [ya(1)
       yb(1)-2];
end
%--------------------------------
function g = guess(x) % initial guess for y and y'
g = [sin(x)
     cos(x)];
end

Answer 1

[Sam Chak]

Hi @lvlv sun

Add these two lines to code as shown below to get the desired number of points for the solution.

numpts  = 5;    % desired number of points
xmesh   = linspace(0,pi/2, numpts);
solinit = bvpinit(xmesh, @guess);

sol     = bvp4c(@bvpfcn, @bcfcn, solinit)

sol = struct with fields:
    solver: 'bvp4c'
         x: [0 0.1963 0.3927 0.7854 1.1781 1.3744 1.5708]
         y: [2x7 double]
        yp: [2x7 double]
     stats: [1x1 struct]

%% ----- add these 2 lines -----
x   = linspace(0,pi/2, numpts);
y   = deval(sol, x)

y = 2x5

0 0.7654 1.4142 1.8477 2.0000 2.0000 1.8478 1.4142 0.7654 0.0001

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%% ----- add these 2 lines -----

function dydx = bvpfcn(x,y) % equation to solve
dydx = zeros(2,1);
dydx = [y(2)
       -y(1)];
end
%--------------------------------
function res = bcfcn(ya,yb) % boundary conditions
res = [ya(1)
       yb(1)-2];
end
%--------------------------------
function g = guess(x) % initial guess for y and y'
g = [sin(x)
     cos(x)];
end