[petsc-users] Questions about TS

2011-10-19 Thread Jed Brown
On Wed, Oct 19, 2011 at 21:39, Blaise Bourdin wrote: > OK, this is clear. It will be really nice indeed when everything is > reorganized this way. > Note that most methods work this way already. The main hole right now is that explicit methods don't support nontrivial mass matrices. The best err

[petsc-users] Questions about TS

2011-10-19 Thread Blaise Bourdin
On Oct 19, 2011, at 4:13 PM, Sean Farley wrote: > Is it right to think of the division between ODE, DAE and IMEX in the > documentation as Fully Explicit vs. Fully implicit vs. Semi-implicit? > > Mostly, yes. Indeed, we made 'shortcuts' such as "if the user provides no > IFunction, then treat

[petsc-users] Questions about TS

2011-10-19 Thread Blaise Bourdin
On Oct 19, 2011, at 4:16 PM, Jed Brown wrote: > On Wed, Oct 19, 2011 at 16:08, Blaise Bourdin wrote: > I get it now... My confusion was due to being used to derived all scheme on > the pde, then discretizing, whereas the documentation assumes that the > equation is already discretized. I shoul

[petsc-users] Questions about TS

2011-10-19 Thread Jed Brown
On Wed, Oct 19, 2011 at 16:08, Blaise Bourdin wrote: > I get it now... My confusion was due to being used to derived all scheme on > the pde, then discretizing, whereas the documentation assumes that the > equation is already discretized. I should have figured it out. > For software purposes and

[petsc-users] Questions about TS

2011-10-19 Thread Sean Farley
> > Is it right to think of the division between ODE, DAE and IMEX in the > documentation as Fully Explicit vs. Fully implicit vs. Semi-implicit? > Mostly, yes. Indeed, we made 'shortcuts' such as "if the user provides no IFunction, then treat it as udot = F(u,t)" and "if the user provides no RHS,

[petsc-users] Questions about TS

2011-10-19 Thread Blaise Bourdin
Dear Jed, I get it now... My confusion was due to being used to derived all scheme on the pde, then discretizing, whereas the documentation assumes that the equation is already discretized. I should have figured it out. Is it right to think of the division between ODE, DAE and IMEX in the doc

[petsc-users] Questions about TS

2011-10-19 Thread Matthew Knepley
On Wed, Oct 19, 2011 at 3:54 PM, Blaise Bourdin wrote: > Hi, > > I am trying to use TS to solve a simple transient problem in an > unstructured finite element f90 code. > > 1. Section 6.1.1 of the manual refers to a TSSetMatrices function that can > be used to set the RHS and LHS matrices, but I c

[petsc-users] Questions about TS

2011-10-19 Thread Jed Brown
On Wed, Oct 19, 2011 at 12:32, Blaise Bourdin wrote: > Hi, > > > > On Wed, Oct 19, 2011 at 10:54, Blaise Bourdin > wrote: > > Hi, > > > > I am trying to use TS to solve a simple transient problem in an > unstructured finite element f90 code. > > > > 1. Section 6.1.1 of the manual refers to a TSS

[petsc-users] Questions about TS

2011-10-19 Thread Blaise Bourdin
Hi, > On Wed, Oct 19, 2011 at 10:54, Blaise Bourdin wrote: > Hi, > > I am trying to use TS to solve a simple transient problem in an unstructured > finite element f90 code. > > 1. Section 6.1.1 of the manual refers to a TSSetMatrices function that can be > used to set the RHS and LHS matrice

[petsc-users] Questions about TS

2011-10-19 Thread Jed Brown
On Wed, Oct 19, 2011 at 10:54, Blaise Bourdin wrote: > Hi, > > I am trying to use TS to solve a simple transient problem in an > unstructured finite element f90 code. > > 1. Section 6.1.1 of the manual refers to a TSSetMatrices function that can > be used to set the RHS and LHS matrices, but I ca

[petsc-users] Questions about TS

2011-10-19 Thread Blaise Bourdin
Hi, I am trying to use TS to solve a simple transient problem in an unstructured finite element f90 code. 1. Section 6.1.1 of the manual refers to a TSSetMatrices function that can be used to set the RHS and LHS matrices, but I can;t find it. Is this section outdated? 2. Since we are using uns