New test for fermion flow and some doc.

test/dirac/test_adapt_ferm.jl

@@ -0,0 +1,48 @@
+using LatticeGPU, Test, CUDA
+
+T = Float64
+lp = SpaceParm{4}((16,16,16,16), (4,4,4,4), BC_PERIODIC, (0,0,0,0,0,0))
+gp = GaugeParm{T}(SU3{T}, 6.1, 1.0)
+dpar = DiracParam{T}(SU3fund,1.3,0.9,(1.0,1.0,1.0,1.0),0.0,0.0)
+ymws = YMworkspace(SU3, T, lp)
+dws = DiracWorkspace(SU3fund,T,lp);
+
+randomize!(ymws.mom, lp, ymws)
+U = exp.(ymws.mom)
+
+psi = scalar_field(Spinor{4,SU3fund{T}},lp);
+pfrandomize!(psi,lp)
+
+Ucp = deepcopy(U)
+psicp = deepcopy(psi)
+# First Integrate very precisely up to t=2 (Wilson)
+println(" # Very precise integration ")
+wflw = wfl_rk3(Float64, 0.0004, 1.0E-7)
+flw(U,psi, wflw, 5000, gp,dpar, lp, ymws, dws)
+pl_exact = Eoft_plaq(U, gp, lp, ymws)
+cl_exact = Eoft_clover(U, gp, lp, ymws)
+println("  - Plaq:   ", pl_exact)
+println("  - Clover: ", cl_exact)
+Ufin = deepcopy(U)
+psifin = deepcopy(psi)
+
+
+# Now use Adaptive step size integrator:
+for tol in (1.0E-4, 1.0E-5, 1.0E-6, 1.0E-7, 1.0E-8)
+    local wflw = wfl_rk3(Float64, 0.0001, tol)
+    U .= Ucp
+    psi .= psicp
+    ns, eps = flw_adapt(U,psi, wflw, 2.0, gp,dpar,lp, ymws,dws)
+    pl = Eoft_plaq(U, gp, lp, ymws)
+    cl = Eoft_clover(U, gp, lp, ymws)
+    psierr = sum(norm2.((psi.-psifin)))./prod(lp.iL)
+
+    println(" # Adaptive integrator (tol=$tol): ", ns, " steps")
+    U .= U ./ Ufin
+    maxd = CUDA.mapreduce(dev_one, max, U, init=0.0)
+    println("  - Plaq:   ", pl," [diff: ", abs(pl-pl_exact), "; ",
+            maxd, "]")
+    println("  - Clover: ", cl, " [diff: ", abs(cl-cl_exact), "; ",
+            maxd, "]")
+    println("  - Fermion diff: ", psierr)
+end