forgot to thank you for this. it worked. your help was much appreciated.

forgot to thank you for this. it worked. your help was much appreciated.

o looks like i uploaded the wrong picture. Here's the one with two DE's. I figured out the problem was i had too many ICs. I removed D(m)(0)=0 and now it only solves for the first point, t=0, and now i get this error.

DBM-variablemass.mw