Undefined function 'fimplicit' for input arguments of type 'sym'

The following example program is available in the 'Solve System of Algebraic Equations': (link: https://in.mathworks.com/help/symbolic/solve-a-system-of-algebraic-equations.html) But whenever run this program in matlab, it replies with an error "Undefined function 'fimplicit' for input arguments of type 'sym'." How to solve it???

syms x y eqn1 = sin(x)+cos(y) == 4/5; eqn2 = sin(x)*cos(y) == 1/10; a = axes; fimplicit(eqn1,[-2*pi 2*pi],'b'); hold on grid on fimplicit(eqn2,[-2*pi 2*pi],'m'); L = sym(-2*pi:pi/2:2*pi); a.XTick = double(L); a.YTick = double(L); M = arrayfun(@char, L, 'UniformOutput', false); a.XTickLabel = M; a.YTickLabel = M; title('Plot of System of Equations') legend('sin(x)+cos(y) == 4/5','sin(x)*cos(y) == 1/10', 'Location', 'best')

Please help me....

Answer 1

[Steven Lord]

That function was introduced in release R2016b of Symbolic Math Toolbox. You're probably using an earlier release. Looking at the "Functionality being removed or changed" table, in earlier releases you can use ezplot. Note, however, that the syntax of those two functions may be different and ezplot may not have all the functionality of fimplicit.

[VELMURUGAN]

Thank you Sir....

[huazai2020]

This is my codes:

clc; clear all;

A=[2 1;1,2]; %Ellipse equation matrix

y=[1;0.5]; %External point

Aroot=chol(A);

L=Aroot\eye(2);

z=Aroot\trustregprob(L.'*L, L.'*y,1);

ellipsefun=@(p,q) sum([p;q].*(A*[p;q]))-1 ;

hold on

ezplot(ellipsefun, [-1 1.3 -1 1.3])

plot(y(1),y(2),'rx',z(1),z(2),'bo');

axis equal

hold off

I use the ezplot, but it gives me some errors below, what is the reason？

Warning: Function failed to evaluate on array inputs; vectorizing the function may

speed up its evaluation and avoid the need to loop over array elements.

> In specgraph\private\ezplotfeval at 57

In ezplot>ezimplicit at 258

In ezplot at 154