Phase plane of a differential system

Hi, i'm trying to plot a phase plane but it doesn't work :(

This is the matlab code:

clear all

clc
[X,Y] = meshgrid(0:0.2:5,0:0.2:5);

u = -((3*X)/(2+X))*(Y-X);

v = zeros(26);

figure

quiver(X,Y,u,v);

And matlab answer me: Warning: Matrix is singular to working precision.

Thank you very much for your help !!!

Answer 1

[Star Strider]

You need to do element-wise (array) operations.

Change the ‘u’ assignment to:

u = -((3*X)./(2+X)).*(Y-X);

and it works.

See the documentation on Array vs. Matrix Operations for details on the differences.

Answer 2

[abc abc]

thank you very much it works :)

[Star Strider]

My pleasure!