Need help in defining mesh size and solver doesn't work well

[A123-bansal123]

Hello sir

1. If I am using this mesh in my code"https://www.firedrakeproject.org/demos/immersed_fem.py.html"
   Then how I can define my h is a function that indicates the local mesh size

2. One more question: If I am solving non linear navier stokes equation as:

up = Function(Z)
# solve the system
solve(F == 0, up, bc, solver_parameters={"newton_solver":{"linear_solver":'mumps'}, "newton_solver":{"relative_tolerance":1e-7}})
u, p, rho = up.subfunctions

error:

Fatal Python error: Cannot recover from stack overflow.
Python runtime state: initialized

Thread 0x000014d60932f700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Thread 0x000014d609535700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Thread 0x000014d609780700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Thread 0x000014d609986700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Thread 0x000014d609bc7700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Thread 0x000014d609e48700 (most recent call first):
  File "/home/aparna/software/firedrake/lib/python3.8/site-packages/pytools/__init__.py", line 2611 in _log_start_if_long
  File "/usr/lib/python3.8/threading.py", line 870 in run
  File "/usr/lib/python3.8/threading.py", line 932 in _bootstrap_inner
  File "/usr/lib/python3.8/threading.py", line 890 in _bootstrap

Current thread 0x000014d626b34740 (most recent call first):
  File "/home/aparna/software/firedrake/src/ufl/ufl/algorithms/map_integrands.py", line 57 in map_integrands
  File "/home/aparna/software/firedrake/src/ufl/ufl/algorithms/map_integrands.py", line 65 in map_integrand_dags
  File "/home/aparna/software/firedrake/src/ufl/ufl/algorithms/apply_algebra_lowering.py", line 173 in apply_algebra_lowering
  File "/home/aparna/software/firedrake/src/ufl/ufl/algorithms/ad.py", line 40 in expand_derivatives
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 313 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 303 in __complex__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 53 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 329 in _call
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 290 in _ufl_evaluate_scalar_
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/expr.py", line 295 in __float__
  File "/home/aparna/software/firedrake/src/ufl/ufl/core/terminal.py", line 51 in evaluate
  File "/home/aparna/software/firedrake/src/ufl/ufl/exproperators.py", line 319 in _eval
  ...
Aborted (core dumped)

How I resolved this error ? Please help me in resolving it. If you need more information, I can provide you. Hope to hear as soon as possible.