Hi, Wolfgang, I am still unclear about what is happening. That zero is just a typo. Even if I remove the zero, these two methods can not get the same solution. What I did is just using two methods to calculate the right-hand side generated by time discretization. One way is to form a mass matrix then time the old solution, the other way is to form the local right-hand side in element level then assemble it into system right-hand side array.
Best, Xiang On Tuesday, 7 April 2020 13:22:55 UTC-7, Wolfgang Bangerth wrote: > > On 4/5/20 12:32 AM, Xiang Sun wrote: > > For correction, the right code for the second method is > > [...] > > Are you saying that you solved your own problem? Or are you still unclear > what > is happening? > > Best > W. > > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > <javascript:> > www: http://www.math.colostate.edu/~bangerth/ > > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/8c36b7a6-7fd0-4976-8aea-d6a52ab28670%40googlegroups.com.
