func (g *Grid2D) Init(lx, ly float64, nx, ny int) {
g.Lx, g.Ly = lx, ly
g.Nx, g.Ny, g.N = nx, ny, nx*ny
g.Dx, g.Dy = g.Lx/float64(nx-1), g.Ly/float64(ny-1)
g.Dxx, g.Dyy = g.Dx*g.Dx, g.Dy*g.Dy
g.L = utl.IntRange3(0, g.N, g.Nx)
g.R = utl.IntAddScalar(g.L, g.Nx-1)
g.B = utl.IntRange(g.Nx)
g.T = utl.IntAddScalar(g.B, (g.Ny-1)*g.Nx)
}
// ElemBryLocalInds returns the local (element) indices of control points @ boundaries
// (if element would have all surfaces @ boundaries)
func (o *Nurbs) ElemBryLocalInds() (I [][]int) {
switch o.gnd {
case 1:
return
case 2:
I = make([][]int, 2*o.gnd)
nx, ny := o.p[0]+1, o.p[1]+1
I[3] = utl.IntRange3(0, nx*ny, nx)
I[1] = utl.IntAddScalar(I[3], nx-1)
I[0] = utl.IntRange(nx)
I[2] = utl.IntAddScalar(I[0], (ny-1)*nx)
case 3:
I = make([][]int, 2*o.gnd)
chk.Panic("3D NURBS: ElemBryLocalInds: TODO") // TODO
}
return
}