Dear Prof. Bangerth, Thank you very much for the explanation. Interpolation of the initial condition works pretty well!
Thanks & Regards Pawan On Fri, Mar 13, 2020 at 3:55 PM Wolfgang Bangerth <[email protected]> wrote: > On 3/13/20 6:08 AM, Pawan Kumar wrote: > > > > To incorporate adaptive mesh refinement after each time steps in my > ongoing work, I am trying to make follwoing small changes in step-26: > > > > > > i. Initial condition > > > > ii. A rectangular domain > > > > iii. Homogeneous Neumann BC. > > > > > > But I am getting some errors(negative values) in the obtained initial > condition plot. > > That is to be expected. The *projection* of a non-negative function > will, in general, not be a non-negative function. The reason is > essentially the same as when you do a truncated Fourier series of a > discontinuous function: You get Gibb's phenomenon. > > If these negative values bother you, try *interpolating* the initial > conditions instead of projecting them. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > 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/255a21fb-19fa-a7c6-e8d0-17158e75c709%40colostate.edu > . > -- 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/CAM4GQ%2BLm7UUYBMXUN%3DzLfFRBzZ%3D6-QQ5sD7Ngv8dHY53AxeEAw%40mail.gmail.com.
