Solving ODE

[tiago.charters.azevedo at gmail.com]

The prolem that you describe
Solve: y''(t) + y(t) =0
such that:
y(0)=3 & y(pi/2)=3

seems to be boundary value problem (BVP), not an initial conditions problem.
The function lsode solves an initial conditions problem not an  boundary value
problem.

I suggest using the odebvp package which solves a linear BVP. You can get it
from octave-forge. It should work on you octave version

http://octave.sourceforge.net/doc/f/lfdif.html

tca