Seeking help: the direction field are all vertical bars
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First of all, I am sorry for the newbie questions. I have googled everywhere, including you-tube, and still cannot get my direction field correctly.
I am trying to plot the direction field of this differential equation: dy/dt=y*(y-1)(y-2)
Clearly, there are 3 critical points. y=0 & 2 are unstable; y=1 is stable.
[T, Y]=meshgrid(-3:0.1:3, -3:0.1:3)
quiver(T, Y, 1./L, S./L, 0.3), axis tight
xlabel 't', ylabel 'y'
title 'Direction Field for dy/dt = y(y-1)(y-2)'
Below is what I got. I don't understand why most part are just vertical bars. I cannot see the trend at all. I have played with changing some parameters in the code and it still didn't come out nicely. Thank you very much for your help. I greatly appreciate it.