dg1d: Add Bsplines1
Continuation of !210 (merged)
This adds a dispatch type Bspline1
similar to Bspline2
. Based on this we implement the necessary method to be able to use it in DGElement
.
I also fixed a subtle bug in the quadrature rules I used in some of the Bspline
methods.
That is, I accidentally used a LG rule with Npts=2
, which corresponds to a N=Npts-1=1
order rule that is exact for polynomials up to 2*N=2
order.
But for Bspline2
we encounter fourth order polynomials, so we should be using Npts=3
.
Also adds a new option to the Mesh
parameters section:
-
kind = "modal_bspline1"
: Utilize a 1st order modal Bspline Ansatz for the DG evolution.