Source code for ffcx.parameters

# Copyright (C) 2005-2020 Anders Logg, Michal Habera, Jack S. Hale
#
# This file is part of FFCx. (https://www.fenicsproject.org)
#
# SPDX-License-Identifier:    LGPL-3.0-or-later

import functools
import json
import logging
import os
import os.path
import pprint
from typing import Optional, Dict, Any
from pathlib import Path

logger = logging.getLogger("ffcx")

FFCX_DEFAULT_PARAMETERS = {
    "epsilon":
        (1e-14, "Machine precision, used for dropping zero terms in tables"),
    "scalar_type":
        ("double", """Scalar type used in generated code. Any of real or complex C floating-point types, e.g.
                      float, double, float _Complex, double _Complex, ..."""),
    "tabulate_tensor_void":
        (False, "True to generate empty tabulation kernels."),
    "table_rtol":
        (1e-6, "Relative precision to use when comparing finite element table values for table reuse."),
    "table_atol":
        (1e-9, "Absolute precision to use when comparing finite element table values for reuse."),
    "assume_aligned":
        (-1, """Assumes alignment (in bytes) of pointers to tabulated tensor, coefficients and constants array.
               This value must be compatible with alignment of data structures allocated outside FFC.
               (-1 means no alignment assumed, safe option)"""),
    "padlen":
        (1, "Pads every declared array in tabulation kernel such that its last dimension is divisible by given value."),
    "verbosity":
        (30, "Logger verbosity. Follows standard logging library levels, i.e. INFO=20, DEBUG=10, etc.")
}


@functools.lru_cache(maxsize=None)
def _load_parameters():
    """Load parameters from JSON files."""
    user_config_file = os.getenv("XDG_CONFIG_HOME", default=Path.home().joinpath(".config")) \
        / Path("ffcx", "ffcx_parameters.json")
    try:
        with open(user_config_file) as f:
            user_parameters = json.load(f)
    except FileNotFoundError:
        user_parameters = {}

    pwd_config_file = Path.cwd().joinpath("ffcx_parameters.json")
    try:
        with open(pwd_config_file) as f:
            pwd_parameters = json.load(f)
    except FileNotFoundError:
        pwd_parameters = {}

    return (user_parameters, pwd_parameters)


[docs]def get_parameters(priority_parameters: Optional[dict] = None) -> dict: """Return (a copy of) the merged parameter values for FFCX. Parameters ---------- priority_parameters: take priority over all other parameter values (see notes) Returns ------- dict: merged parameter values Notes ----- This function sets the log level from the merged parameter values prior to returning. The `ffcx_parameters.json` files are cached on the first call. Subsequent calls to this function use this cache. Priority ordering of parameters from highest to lowest is: - **priority_parameters** (API and command line parameters) - **$PWD/ffcx_parameters.json** (local parameters) - **$XDG_CONFIG_HOME/ffcx/ffcx_parameters.json** (user parameters) - **FFCX_DEFAULT_PARAMETERS** in `ffcx.parameters` `XDG_CONFIG_HOME` is `~/.config/` if the environment variable is not set. Example `ffcx_parameters.json` file: { "assume_aligned": 32, "epsilon": 1e-7 } """ parameters: Dict[str, Any] = {} for param, (value, _) in FFCX_DEFAULT_PARAMETERS.items(): parameters[param] = value # NOTE: _load_parameters uses functools.lru_cache user_parameters, pwd_parameters = _load_parameters() parameters.update(user_parameters) parameters.update(pwd_parameters) if priority_parameters is not None: parameters.update(priority_parameters) logger.setLevel(parameters["verbosity"]) logger.info("Final parameter values") logger.info(pprint.pformat(parameters)) return parameters