Mathematica 9 is now available
Student Support Forum
-----
Student Support Forum: 'Re: numerical solution to differential equation' topicStudent Support Forum > General > "Re: numerical solution to differential equation"

Help | Reply To Topic
Author Comment/Response
Forum Moderator
email me
04/23/97 3:40pm

Reply to message #322 from haidong chang: > I have been trying to
solve this equation numerically > > NDSolve[{y'[t]==((1-y)*Exp[-x-a*t]*Exp[b*y])-(y*Exp[-z+c*t]*Exp[d*y]),
y[0]==0}, y, {t, 0, 4}] > > a, b, c, d, x and z are constants. > >
I get this message: > > NDSolve::ndnum:The right hand side of the
differential equation does not evaluate to a number at t==0 > > How
can I solve this? The correct value at t==0 would be y[0]->0 (It is
zero to 10 decimal places) > > thankyou > > haidong ________________
^^^^^^^^^^^^^^^^ Try refering to y as y[t] on the rhs of your equation:
NDSolve[{y'[t]==((1-y[t])*Exp[-x-a*t]*Exp[b*y[t]])-(y[t]*Exp[-z+c*t]*Exp[d*y[t]]),
y[0]==0}, y, {t, 0, 4}] Forum Moderator


URL: ,
Help | Reply To Topic