re added upwind_order

Author: xtalax

src/MOLFiniteDifference.jl

@@ -2,14 +2,15 @@ struct MOLFiniteDifference{G} <: DiffEqBase.AbstractDiscretization
     dxs
     time
     approx_order::Int
+    upwind_order::Int
     grid_align::G
 end
 
 # Constructors. If no order is specified, both upwind and centered differences will be 2nd order
-function MOLFiniteDifference(dxs, time=nothing; approx_order = 2, grid_align=CenterAlignedGrid())
+function MOLFiniteDifference(dxs, time=nothing; approx_order = 2, upwind_order = 1, grid_align=CenterAlignedGrid())
 
     if approx_order % 2 != 0
         @warn "Discretization approx_order must be even, rounding up to $(approx_order+1)"
     end
-    return MOLFiniteDifference{typeof(grid_align)}(dxs, time, approx_order, grid_align)
+    return MOLFiniteDifference{typeof(grid_align)}(dxs, time, approx_order, upwind_order, grid_align)
 end