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petsc interface

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This commit is contained in:
Jukka Aho
2015-12-05 10:58:01 +02:00
parent f078330971
commit d4e21af8de
9 changed files with 194 additions and 45 deletions
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src/directsolver.jl
+22 -20
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@@ -1,6 +1,12 @@
# This file is a part of JuliaFEM.
# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
#= Solution norms for piston model
piston_19611_P2.inp iter 1 2.048090408266966
=#
## Direct solver
using JuliaFEM
@@ -32,7 +38,7 @@ function DirectSolver(name="DirectSolver")
1.0e-6, # convergence tolerance
false, # dump matrices
true, # reduce stiffness matrix
:LDLt # method: LDLt or LU ?
:CHOLMOD # method: CHOLMOD, UMFPACK, PETSc_GMRES
)
end
@@ -64,10 +70,9 @@ Solve problem
Cu = g
"""
function solve(K, f, C, g, ::Type{Val{:LDLt}})
function solve(K, f, C, g, ::Type{Val{:CHOLMOD}})
t0 = time()
# make sure K is symmetric
# K = Symmetric(K)
s = maximum(abs(1/2*(K + K') - K))
@@ -84,55 +89,52 @@ function solve(K, f, C, g, ::Type{Val{:LDLt}})
all_dofs = unique(rowvals(K))
interior_dofs = setdiff(all_dofs, boundary_dofs)
info("all dofs = $(length(all_dofs))")
info("interior dofs = $(length(interior_dofs))")
info("boundary dofs = $(length(boundary_dofs))")
info("preparation in ", time()-t0, " seconds")
info("CHOLMOD: all dofs = $(length(all_dofs))")
info("CHOLMOD: interior dofs = $(length(interior_dofs))")
info("CHOLMOD: boundary dofs = $(length(boundary_dofs))")
# solve displacement on known boundary
t0 = time()
LUF = lufact(C[boundary_dofs, boundary_dofs])
u = zeros(dim)
u[boundary_dofs] = LUF \ full(g[boundary_dofs])
info("displacement on boundary solved.")
info("CHOLMOD: displacement on boundary solved.")
normub = norm(u[boundary_dofs])
info("norm[u_boundary_dofs] = ", normub)
if isapprox(normub, 0.0)
info("homogeneous dirichlet boundary")
info("CHOLMOD: homogeneous dirichlet boundary")
end
info("solve boundary = ", time()-t0)
# factorize interior domain using cholmod
t0 = time()
t = time()
CF = cholfact(K[interior_dofs, interior_dofs])
Kib = K[interior_dofs, boundary_dofs]
Kbb = K[boundary_dofs, boundary_dofs]
fi = f[interior_dofs]
info("factorizations done in ", time()-t0, " seconds")
info("CHOLMOD: LDLt factorization done in ", time()-t, " seconds")
# solve interior domain + lagrange multipliers
t0 = time()
u[interior_dofs] = CF \ (fi - Kib*u[boundary_dofs])
la = zeros(dim)
la[boundary_dofs] = LUF \ full(Kib'*u[interior_dofs] - Kbb*u[boundary_dofs])
info("solved interior in ", time()-t0, " seconds. norm = ", norm(u))
info("CHOLMOD: solved in ", time()-t0, " seconds. norm = ", norm(u))
return u, la
end
function solve(K, f, C, g, ::Type{Val{:LU}})
function solve(K, f, C, g, ::Type{Val{:UMFPACK}})
t0 = time()
dim = size(K, 1)
A = nothing
try
A = [K C'; C spzeros(dim, dim)]
catch
info("size(K) = ", size(K))
info("size(C) = ", size(C))
error("Failed to construct problem. dim = $dim")
info("UMFPACK: size(K) = ", size(K))
info("UMFPACK: size(C) = ", size(C))
error("UMFPACK: Failed to construct problem. dim = $dim")
end
b = [f; g]
nz = sort(unique(rowvals(A)))
u = zeros(length(b))
u[nz] = lufact(A[nz,nz]) \ full(b[nz])
info("UMFPACK: solved in ", time()-t0, " seconds. norm = ", norm(u[1:dim]))
return u[1:dim], u[dim+1:end]
end