Julia语言FEniCS周期边界条件

Question

我想在Julia语言的FEniCS中应用一个周期边界条件，但我发现的所有例子都是C++或Python中的。如何使用Julia创建周期边界条件？这似乎很难，因为茱莉亚没有课。这里有一个最小的例子：

using FEniCS
using PyCall
length=2.2
height=0.41
channel = Rectangle(Point([0.0, 0.0]), Point([length, height]))
domain = channel
mesh = generate_mesh(domain, 64)
# insert function here for PeriodicBoundarycondition
Q = FunctionSpace(mesh, "P", 1,constrained_domain=#the function that i am looking for)

Answer 1

我查看了构成FEniCS的julia代码，FEniCS页面上的周期边界条件的示例，以及我为FEniCS编写的一些旧python代码，它启发了我写这篇文章：

using FEniCS
using PyCall
@pyimport fenics
py"""
from dolfin import *
from mshr import *
length=2.2
height=0.41
channel = Rectangle(Point([0.0, 0.0]), Point([length, height]))
domain = channel
mesh = generate_mesh(domain, 64)
subdomains = MeshFunction("size_t", mesh, 1)
subdomains.set_all(0)
class Wall(SubDomain):
def inside(self,x,on_boundary):
return (near(x[1],height) or near(x[1],height)) and on_boundary
wall=Wall()
class PeriodicBoundary(SubDomain):
# Left boundary is "target domain" G
def inside(self, x, on_boundary):
return bool(x[0] < DOLFIN_EPS and x[0] > -DOLFIN_EPS and on_boundary)
# Map right boundary (H) to left boundary (G)
def map(self, x, y):
y[0] = x[0] - length
y[1] = x[1]
pbc=PeriodicBoundary()
"""
Q=FunctionSpace(fenics.VectorFunctionSpace(py"mesh", "P", 1,constrained_domain=py"pbc"))

这个解决方案不是最优的，因为它只是在python中完成了整个事情，但我想我必须接受它。