Why Do Simulated and Theoretical Soliton Collisions Differ?

[hanson]

Hi all.
I am studying the collision of two solitons of the NLS equation.
Actually I just want to plot out the exact solutions given in R.S.Johnson's book. (page 321, figure 4.4).
I have used MATLAB to do this and produced the figure using exactly the same values for the parameters.
However, the produced graph is a little bit different from that in R.S.Johnson's book during collision.
I am wondering what's wrong.

Is there any standard animation available in the internet for the collision of two NLS solitons? This sounds very standard, but I can hardly find any...
Will you have any reference?

 

[Chris Hillman]

Did you check that the function which you input is in fact a solution of the NLS? Did you try plotting/checking it using another package such as Maple or Mathematica?