diff --git a/examples/animate.jl b/examples/animate.jl
index b6b30cb..f427768 100644
--- a/examples/animate.jl
+++ b/examples/animate.jl
@@ -48,6 +48,6 @@ sphprob =  SPHProblem(system, h, H, sphkernel, ρ, v, ptype, ρ₀, m₀, Δt, 
 sphprob.dpc_l₀   = 0.01
 sphprob.dpc_λ    = 0.01
 sphprob.dpc_pmax = 36000
-timesolve!(sphprob; batch = 100, timeframe = 1.1, writetime = 0.01, path = "D:/vtk/", pvc = true, anim = true)
+timesolve!(sphprob; batch = 100, timeframe = 1.1, writetime = 0.001, path = "D:/vtk/", pvc = true, anim = true)
 
 #makedf(sphprob)
\ No newline at end of file
diff --git a/src/celllist.jl b/src/celllist.jl
index a34eb86..79bc53f 100644
--- a/src/celllist.jl
+++ b/src/celllist.jl
@@ -157,7 +157,7 @@ end
 
 Update only distance 
 """
-@noinline function partialupdate!(c::GPUCellList)
+@noinline function partialupdate!(c::GPUCellList, fillzero::Bool = true)
     fill!(c.cnt, zero(Int32))
     if fillzero fill!(c.pairs, (zero(Int32), zero(Int32))) end
     neib_internal_2d!(c.pairs, c.cnt, c.cellpnum, c.points, c.celllist, c.dist)
diff --git a/src/gpukernels2d.jl b/src/gpukernels2d.jl
index b9a7868..649c6fe 100644
--- a/src/gpukernels2d.jl
+++ b/src/gpukernels2d.jl
@@ -751,7 +751,7 @@ Compute ∂Π∂t - artificial viscosity. Add to `∑∂Π∂t`
 
 ```math
 
-\\Pi_{ij} = \\begin{cases} \\frac{- \\alpha \\overline{c}_{ij} \\mu_{ij} + \\beta \\mu_{ij}^2 }{\\overline{\rho}_{ij}} &  \\textbf{v}_{ij}\\cdot \\textbf{r}_{ij} < 0 \\\\ 0 &  otherwise \\end{cases}
+\\Pi_{ij} = \\begin{cases} \\frac{- \\alpha \\overline{c}_{ij} \\mu_{ij} + \\beta \\mu_{ij}^2 }{\\overline{\\rho}_{ij}} &  \\textbf{v}_{ij}\\cdot \\textbf{r}_{ij} < 0 \\\\ 0 &  otherwise \\end{cases}
 
 \\\\
 \\\\