Heat Equation Broken

using DifferentialEquations, Plots
f = (t,x,u)  -> [zeros(size(x,1))    zeros(size(x,1))]
u0_func = (x) -> [float.((abs.(x[:,1]-.5) .< 1e-6) .& (abs.(x[:,2]-.5) .< 1e-6)) float.((abs.(x[:,1]-.5) .< 1e-6) .& (abs.(x[:,2]-.5) .< 1e-6))]  # size (x,2), 2 meaning 2 variables


## Build the mesh
T = (0.0,30.0)
dx = 1//2^(4)
dt = 1//2^(2)
fem_mesh = parabolic_squaremesh([0 1 0 1],dx,dt,T,:neumann)
u0 = u0_func(fem_mesh.node)

## Build the problem type
prob = HeatProblem(u0,f,fem_mesh,D=[.003 .001])

## Solve
sol = solve(prob,alg=FEMDiffEqHeatImplicitEuler(),save_everystep=true,timeseries_steps=1)
animate(sol,"../assets/diffconsts.gif",zlim=(-0.01,.01),cbar=false)