Log(x) equation does not plot correctly

Hello,

Here is my code:

x = -5:0.05:10;

y=log(x);

plot(x,y)

comet(x,y)

It won't let it animate. When i put x = 1:0.05:10; it does animate , but shouldn't matlab do it anyway? Why doesn't it animate from 1 to 10 even if i put -5 , every other function works fine? Maybe comet doesn't work with it?

If you have any ideas, please help.

Answer 1

[Cris LaPierre]

Perhaps reading the error message you get on the screen will help explain the issue:

Warning: Imaginary parts of complex X and/or Y arguments ignored.

Error using matlab.graphics.axis.Axes/set

Complex values are not supported.

When you take the log of numbers <0, you result is complex. Numbers >0 are not. Comet does not support complex numbers. Consider instead using the magnitude: comet(x,abs(y)) or the real part: comet(x,real(y))

[Jelena Zlatanovic]

Thank you!

Answer 2

[VBBV]

%f true
 comet(x,real(y))

Use the real components to graph.