From: Terry on
Here's my code:

>>sol = dsolve('Dy1=y2','Dy2=-y1 + 0.1*y1^3','y1(0)=0','y2(0)=1')

>>s1 = simple(sol.y1)
>>s2 = simple(sol.y2)

>>ezplot(sol.y1, [0,20])
>>hold on
>>ezplot(sol.y2, [0,20])
>>hold off

and here's the error:

"Error using ==> dsolve
Error, (in dsolve/IC) The 'implicit' option is not available when
giving Initial Conditions."

I believe the code is mostly correct, but obviously has at least one
mistake.

Thanks for the help.