Hi,

I found a small bug in the DG/HDG Splitting iTutorial (Unit 3.4). In input block 7 there is the function:

```
def SolveConvectionSteps(gfuvec, res, tau, steps):
bfmixed.Apply (gfuvec, gfuL2.vec)
VL2.SolveM(CoefficientFunction(1), gfuL2.vec)
conv_applied = gfuL2.vec.CreateVector()
for i in range(steps):
convL2.Apply(gfuL2.vec,conv_applied)
VL2.SolveM(CoefficientFunction(1), conv_applied)
gfuL2.vec.data -= tau/steps * conv_applied
#Redraw()
bfmixedT.Apply (gfuL2.vec, res)
```

The two calls to SolveM give:

TypeError: SolveM(): incompatible function arguments. The following argument types are supported:

1. (self: ngsolve.comp.FESpace, vec: ngsolve.la.BaseVector, rho: ngsolve.fem.CoefficientFunction=None) → None

The error can be fixed by reversing the order of the arguments to SolveM or providing keywords like this:

`VL2.SolveM(rho=CoefficientFunction(1), vec=conv_applied)`

Edit: The same error is present in block 9 of the DG-method for convection (Unit 3.3)

Best,

Dow