Question #103034 on DOLFIN changed: https://answers.launchpad.net/dolfin/+question/103034
Murtazo Nazarov posted a new comment: Murtazo Nazarov wrote: > Your question #103034 on DOLFIN changed: > https://answers.launchpad.net/dolfin/+question/103034 > > Status: Answered => Open > > You are still having a problem: > Anders Logg wrote: > >> Question #103034 on DOLFIN changed: >> https://answers.launchpad.net/dolfin/+question/103034 >> >> Status: Open => Answered >> >> Anders Logg proposed the following answer: >> On Wed, Mar 03, 2010 at 02:36:59AM -0000, Murtazo Nazarov wrote: >> >> >>> New question #103034 on DOLFIN: >>> https://answers.launchpad.net/dolfin/+question/103034 >>> >>> Hi, >>> >>> I am wondering how to compute an L1-norm, and L_inf norm of a functional on >>> the cell. For instance how to compute >>> >>> 1. ||\div(Pu)||_{L_\infty} ? >>> >>> >> Try projecting div(Pu) onto piecewise constants and then pick the >> largest absolute value in the vector. >> >> >> > > I need L_inf norm on the cell. With this way, doesn't give the L_inf for > the entire domain? > > murtazo > > Instead of projecting div(Pu) onto piecewise constants, I projected it into dG(1), with this way I get three values on each cell, which I can then pick up the largest of them. That gives me then L_inf_K, where K is a cell. Now, I cannot figured out how is the numbering done for the dG(1) elements. If N is a total number of cells, then my projected vector Pdg has 3*N elements. How can I pick up elements of Pdg in the cell K? Thanks, murtazo >>> 2. ||\div(Pu)||_{L_1} ? >>> >>> >> Try >> >> M = abs(div(Pu))*dx >> >> -- >> Anders >> >> >> >> >>> where u is velocity (vector) and P is pressure (scalar). L2 norm is obvious >>> to do. >>> >>> I use C++ interface >>> >>> >>> >> > > -- You received this question notification because you are a member of DOLFIN Team, which is an answer contact for DOLFIN. _______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : [email protected] Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
