LSR/env/lib/python3.6/site-packages/control/config.py
2020-06-04 17:24:47 +02:00

159 lines
5.5 KiB
Python

# config.py - package defaults
# RMM, 4 Nov 2012
#
# This file contains default values and utility functions for setting
# variables that control the behavior of the control package.
# Eventually it will be possible to read and write configuration
# files. For now, you can just choose between MATLAB and FBS default
# values + tweak a few other things.
import warnings
__all__ = ['defaults', 'set_defaults', 'reset_defaults',
'use_matlab_defaults', 'use_fbs_defaults',
'use_numpy_matrix']
# Package level default values
_control_defaults = {
# No package level defaults (yet)
}
defaults = dict(_control_defaults)
def set_defaults(module, **keywords):
"""Set default values of parameters for a module.
The set_defaults() function can be used to modify multiple parameter
values for a module at the same time, using keyword arguments:
control.set_defaults('module', param1=val, param2=val)
"""
if not isinstance(module, str):
raise ValueError("module must be a string")
for key, val in keywords.items():
defaults[module + '.' + key] = val
def reset_defaults():
"""Reset configuration values to their default (initial) values."""
# System level defaults
defaults.update(_control_defaults)
from .freqplot import _bode_defaults, _freqplot_defaults
defaults.update(_bode_defaults)
defaults.update(_freqplot_defaults)
from .nichols import _nichols_defaults
defaults.update(_nichols_defaults)
from .pzmap import _pzmap_defaults
defaults.update(_pzmap_defaults)
from .rlocus import _rlocus_defaults
defaults.update(_rlocus_defaults)
from .statesp import _statesp_defaults
defaults.update(_statesp_defaults)
def _get_param(module, param, argval=None, defval=None, pop=False):
"""Return the default value for a configuration option.
The _get_param() function is a utility function used to get the value of a
parameter for a module based on the default parameter settings and any
arguments passed to the function. The precedence order for parameters is
the value passed to the function (as a keyword), the value from the
config.defaults dictionary, and the default value `defval`.
Parameters
----------
module : str
Name of the module whose parameters are being requested.
param : str
Name of the parameter value to be determeind.
argval : object or dict
Value of the parameter as passed to the function. This can either be
an object or a dictionary (i.e. the keyword list from the function
call). Defaults to None.
defval : object
Default value of the parameter to use, if it is not located in the
`config.defaults` dictionary. If a dictionary is provided, then
`module.param` is used to determine the default value. Defaults to
None.
pop : bool
If True and if argval is a dict, then pop the remove the parameter
entry from the argval dict after retreiving it. This allows the use
of a keyword argument list to be passed through to other functions
internal to the function being called.
"""
# Make sure that we were passed sensible arguments
if not isinstance(module, str) or not isinstance(param, str):
raise ValueError("module and param must be strings")
# Construction the name of the key, for later use
key = module + '.' + param
# If we were passed a dict for the argval, get the param value from there
if isinstance(argval, dict):
argval = argval.pop(param, None) if pop else argval.get(param, None)
# If we were passed a dict for the defval, get the param value from there
if isinstance(defval, dict):
defval = defval.get(key, None)
# Return the parameter value to use (argval > defaults > defval)
return argval if argval is not None else defaults.get(key, defval)
# Set defaults to match MATLAB
def use_matlab_defaults():
"""Use MATLAB compatible configuration settings.
The following conventions are used:
* Bode plots plot gain in dB, phase in degrees, frequency in
Hertz, with grids
* State space class and functions use Numpy matrix objects
"""
set_defaults('bode', dB=True, deg=True, Hz=True, grid=True)
set_defaults('statesp', use_numpy_matrix=True)
# Set defaults to match FBS (Astrom and Murray)
def use_fbs_defaults():
"""Use `Feedback Systems <http://fbsbook.org>`_ (FBS) compatible settings.
The following conventions are used:
* Bode plots plot gain in powers of ten, phase in degrees,
frequency in Hertz, no grid
"""
set_defaults('bode', dB=False, deg=True, Hz=False, grid=False)
# Decide whether to use numpy.matrix for state space operations
def use_numpy_matrix(flag=True, warn=True):
"""Turn on/off use of Numpy `matrix` class for state space operations.
Parameters
----------
flag : bool
If flag is `True` (default), use the Numpy (soon to be deprecated)
`matrix` class to represent matrices in the `~control.StateSpace`
class and functions. If flat is `False`, then matrices are
represented by a 2D `ndarray` object.
warn : bool
If flag is `True` (default), issue a warning when turning on the use
of the Numpy `matrix` class. Set `warn` to false to omit display of
the warning message.
"""
if flag and warn:
warnings.warn("Return type numpy.matrix is soon to be deprecated.",
stacklevel=2)
set_defaults('statesp', use_numpy_matrix=flag)