#!/usr/bin/env python
# -------------------------------------------------------------------------------
# ____ _ _____ ____ _
# | _ \ _ _| | |_ _/ ___| _ __ (_) ___ ___
# | |_) | | | | | | | \___ \| '_ \| |/ __/ _ \
# | __/| |_| | |___| | ___) | |_) | | (_| __/
# |_| \__, |_____|_| |____/| .__/|_|\___\___|
# |___/ |_|
#
# Name: sim_batch.py
# Purpose: Tool used to launch LTSpice simulation in batch mode. Netlists can
# be updated by user instructions
#
# Author: Nuno Brum (nuno.brum@gmail.com)
#
# Licence: refer to the LICENSE file
# -------------------------------------------------------------------------------
"""
** This class is still maintained for backward compatibility. The user is invited to use the SpiceEditor and SimRunner
classes instead. These give more flexibility in the command of simulations.**
Allows launching LTSpice simulations from a Python Script, thus allowing to overcome the 3 dimensions STEP limitation on
LTSpice, update resistor values, or component models.
The code snipped below will simulate a circuit with two different diode models, set the simulation
temperature to 80 degrees, and update the values of R1 and R2 to 3.3k. ::
LTC = SimCommander("my_circuit.asc")
LTC.set_parameters(temp=80) # Sets the simulation temperature to be 80 degrees
LTC.set_component_value('R2', '3.3k') # Updates the resistor R2 value to be 3.3k
for dmodel in ("BAT54", "BAT46WJ"):
LTC.set_element_model("D1", model) # Sets the Diode D1 model
for res_value in sweep(2.2, 2,4, 0.2): # Steps from 2.2 to 2.4 with 0.2 increments
LTC.set_component_value('R1', res_value) # Updates the resistor R1 value to be 3.3k
LTC.run()
LTC.wait_completion() # Waits for the LTSpice simulations to complete
print("Total Simulations: {}".format(LTC.runno))
print("Successful Simulations: {}".format(LTC.okSim))
print("Failed Simulations: {}".format(LTC.failSim))
The first line will create an python class instance that represents the LTSpice file or netlist that is to be
simulated. This object implements methods that are used to manipulate the spice netlist. For example, the method
set_parameters() will set or update existing parameters defined in the netlist. The method set_component_value() is
used to update existing component values or models.
---------------
Multiprocessing
---------------
For making better use of today's computer capabilities, the SimCommander spawns several LTSpice instances
each executing in parallel a simulation.
By default, the number of parallel simulations is 4, however the user can override this in two ways. Either
using the class constructor argument ``parallel_sims`` or by forcing the allocation of more processes in the
run() call by setting ``wait_resource=False``. ::
LTC.run(wait_resource=False)
The recommended way is to set the parameter ``parallel_sims`` in the class constructor. ::
LTC=SimCommander("my_circuit.asc", parallel_sims=8)
The user then can launch a simulation with the updates done to the netlist by calling the run() method. Since the
processes are not executed right away, but rather just scheduled for simulation, the wait_completion() function is
needed if the user wants to execute code only after the completion of all scheduled simulations.
The usage of wait_completion() is optional. Just note that the script will only end when all the scheduled tasks are
executed.
---------
Callbacks
---------
As seen above, the `wait_completion()` can be used to wait for all the simulations to be finished. However, this is
not efficient from a multiprocessor point of view. Ideally, the post-processing should be also handled while other
simulations are still running. For this purpose, the user can use a function call back.
The callback function is called when the simulation has finished directly by the thread that has handling the
simulation. A function callback receives two arguments.
The RAW file and the LOG file names. Below is an example of a callback function::
def processing_data(raw_filename, log_filename):
'''This is a call back function that just prints the filenames'''
print("Simulation Raw file is %s. The log is %s" % (raw_filename, log_filename)
# Other code below either using LTSteps.py or raw_read.py
log_info = LTSpiceLogReader(log_filename)
rise, measures = log_info.dataset["rise_time"]
The callback function is optional. If no callback function is given, the thread is terminated just after the
simulation is finished.
"""
__author__ = "Nuno Canto Brum <nuno.brum@gmail.com>"
__copyright__ = "Copyright 2020, Fribourg Switzerland"
import logging
import os
from collections.abc import Callable
from pathlib import Path
from typing import Any
_logger = logging.getLogger("spicelib.SimBatch")
from PyLTSpice.editor.spice_editor import SpiceEditor as BaseSpiceEditor
from spicelib.sim.simulator import Simulator
from spicelib.sim.run_task import RunTask
from spicelib.sim.sim_runner import SimRunner
END_LINE_TERM = '\n'
[docs]
class SimCommander(BaseSpiceEditor):
"""
*(Deprecated)*
Backwards compatibility class.
This class will be soon deprecated. For a better control of the simulation environment, supporting other simulators
and allowing to simulate directly the .ASC files, the SpiceEditor class is now separated from the Simulator Running
class.
Please check the SimRunner class for more information.
"""
def __init__(self, netlist_file: str | Path, parallel_sims: int = 4, timeout=None, verbose=False,
encoding='autodetect', simulator=None):
if simulator is None:
from ..sim.ltspice_simulator import LTspice # In case no simulator is given
simulator = LTspice
netlist_file = Path(netlist_file)
self.netlist_file = netlist_file # Legacy property
if netlist_file.suffix == '.asc':
netlist_file = simulator.create_netlist(netlist_file)
super().__init__(netlist_file, encoding)
self.runner = SimRunner(simulator=simulator, parallel_sims=parallel_sims, timeout=timeout, verbose=verbose,
output_folder=netlist_file.parent.as_posix())
[docs]
def setLTspiceRunCommand(self, spice_tool: str | type[Simulator]) -> None:
"""
*(Deprecated)*
Manually setting the LTSpice run command.
:param spice_tool: String containing the path to the spice tool to be used, or alternatively the Simulator
object.
:return: Nothing
:rtype: None
"""
self.runner.set_run_command(spice_tool)
[docs]
def add_LTspiceRunCmdLineSwitches(self, *args) -> None:
"""
*(Deprecated)*
Used to add an extra command line argument such as -I<path> to add symbol search path or -FastAccess
to convert the raw file into Fast Access.
The arguments is a list of strings as is defined in the LTSpice command line documentation.
:param args: list of strings
A list of command line switches such as "-ascii" for generating a raw file in text format or "-alt" for
setting the solver to alternate. See Command Line Switches information on LTSpice help file.
:type args: list[str]
:returns: Nothing
"""
self.runner.clear_command_line_switches()
for option in args:
self.runner.add_command_line_switch(option)
[docs]
def run(self, wait_resource: bool = True, callback: Callable[[str, str], Any] = None, timeout: float = 600,
run_filename: str = None, simulator=None):
return self.runner.run(self, wait_resource=wait_resource, callback=callback, timeout=timeout,
run_filename=run_filename)
[docs]
def updated_stats(self):
"""
*(Deprecated)*
This function updates the OK/Fail statistics and releases finished RunTask objects from memory.
:returns: Nothing
"""
self.runner.active_threads()
return
[docs]
def wait_completion(self, timeout=None, abort_all_on_timeout=False) -> bool:
return self.runner.wait_completion(timeout, abort_all_on_timeout)
@property
def runno(self):
"""*(Deprecated)* Legacy property"""
return self.runner.runno
@property
def okSim(self):
"""*(Deprecated)* Legacy property"""
return self.runner.okSim
@property
def failSim(self):
"""*(Deprecated)* Legacy property"""
return self.runner.failSim
if __name__ == "__main__":
# get script absolute path
meAbsPath = os.path.dirname(os.path.realpath(__file__))
meAbsPath, _ = os.path.split(meAbsPath)
# select spice model
LTC = SimCommander('C:\\sandbox\\PySpice\\tests\\testfile.asc')
# set default arguments
LTC.set_parameters(res=0.001, cap=100e-6)
# define simulation
LTC.add_instructions(
"; Simulation settings",
# [".STEP PARAM Rmotor LIST 21 28"],
".TRAN 3m",
# ".step param run 1 2 1"
)
# do parameter sweep
for res in range(5):
# LTC.runs_to_do = range(2)
LTC.set_parameters(ANA=res)
raw, log = LTC.run().wait_results()
_logger.debug(f"Raw file '{raw}' | Log File '{log}'")
# Sim Statistics
_logger.info(f'Successful/Total Simulations: {LTC.okSim}/{LTC.runno}')
def callback_function(raw_file, log_file):
_logger.debug(f"Handling the simulation data of {raw_file}, log file {log_file}")
LTC = SimCommander(meAbsPath + "\\test_files\\testfile.asc", parallel_sims=1)
tstart = 0
for tstop in (2, 5, 8, 10):
tduration = tstop - tstart
LTC.add_instruction(f".tran {tduration}", )
if tstart != 0:
LTC.add_instruction(f".loadbias {bias_file}")
# Put here your parameter modifications
# LTC.set_parameters(param1=1, param2=2, param3=3)
bias_file = "sim_loadbias_%d.txt" % tstop
LTC.add_instruction(f".savebias {bias_file} internal time={tduration}")
tstart = tstop
LTC.run(callback=callback_function)
LTC.reset_netlist()
LTC.add_instruction('.ac dec 40 1m 1G')
LTC.set_component_value('V1', 'AC 1 0')
LTC.run(callback=callback_function)
LTC.wait_completion()