Module backtrader.observer

Expand source code 
#!/usr/bin/env python
# -*- coding: utf-8; py-indent-offset:4 -*-
###############################################################################
#
# Copyright (C) 2015-2023 Daniel Rodriguez
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
###############################################################################
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)


from .lineiterator import LineIterator, ObserverBase, StrategyBase
from backtrader.utils.py3 import with_metaclass


class MetaObserver(ObserverBase.__class__):
    def donew(cls, *args, **kwargs):
        _obj, args, kwargs = super(MetaObserver, cls).donew(*args, **kwargs)
        _obj._analyzers = list()  # keep children analyzers

        return _obj, args, kwargs  # return the instantiated object and args

    def dopreinit(cls, _obj, *args, **kwargs):
        _obj, args, kwargs = \
            super(MetaObserver, cls).dopreinit(_obj, *args, **kwargs)

        if _obj._stclock:  # Change clock if strategy wide observer
            _obj._clock = _obj._owner

        return _obj, args, kwargs


class Observer(with_metaclass(MetaObserver, ObserverBase)):
    _stclock = False

    _OwnerCls = StrategyBase
    _ltype = LineIterator.ObsType

    csv = True

    plotinfo = dict(plot=False, subplot=True)

    # An Observer is ideally always observing and that' why prenext calls
    # next. The behaviour can be overriden by subclasses
    def prenext(self):
        self.next()

    def _register_analyzer(self, analyzer):
        self._analyzers.append(analyzer)

    def _start(self):
        self.start()

    def start(self):
        pass

Classes

class MetaObserver (*args, **kwargs)

Dirty job manager for a LineSeries

  • During new (class creation), it reads "lines", "plotinfo", "plotlines" class variable definitions and turns them into Classes of type Lines or AutoClassInfo (plotinfo/plotlines)

  • During "new" (instance creation) the lines/plotinfo/plotlines classes are substituted in the instance with instances of the aforementioned classes and aliases are added for the "lines" held in the "lines" instance

    Additionally and for remaining kwargs, these are matched against args in plotinfo and if existent are set there and removed from kwargs

    Remember that this Metaclass has a MetaParams (from metabase) as root class and therefore "params" defined for the class have been removed from kwargs at an earlier state

Expand source code 
class MetaObserver(ObserverBase.__class__):
    def donew(cls, *args, **kwargs):
        _obj, args, kwargs = super(MetaObserver, cls).donew(*args, **kwargs)
        _obj._analyzers = list()  # keep children analyzers

        return _obj, args, kwargs  # return the instantiated object and args

    def dopreinit(cls, _obj, *args, **kwargs):
        _obj, args, kwargs = \
            super(MetaObserver, cls).dopreinit(_obj, *args, **kwargs)

        if _obj._stclock:  # Change clock if strategy wide observer
            _obj._clock = _obj._owner

        return _obj, args, kwargs

Ancestors

Subclasses

Methods

def dopreinit(cls, _obj, *args, **kwargs)
Expand source code 
def dopreinit(cls, _obj, *args, **kwargs):
    _obj, args, kwargs = \
        super(MetaObserver, cls).dopreinit(_obj, *args, **kwargs)

    if _obj._stclock:  # Change clock if strategy wide observer
        _obj._clock = _obj._owner

    return _obj, args, kwargs

Inherited members

class Observer (*args, **kwargs)

Base class for LineXXX instances that hold more than one line

Expand source code 
class Observer(with_metaclass(MetaObserver, ObserverBase)):
    _stclock = False

    _OwnerCls = StrategyBase
    _ltype = LineIterator.ObsType

    csv = True

    plotinfo = dict(plot=False, subplot=True)

    # An Observer is ideally always observing and that' why prenext calls
    # next. The behaviour can be overriden by subclasses
    def prenext(self):
        self.next()

    def _register_analyzer(self, analyzer):
        self._analyzers.append(analyzer)

    def _start(self):
        self.start()

    def start(self):
        pass

Ancestors

Subclasses

Class variables

var alias
var aliased
var csv
var frompackages
var linealias
var packages
var params
var plotinfo
var plotlines

Methods

def start(self)
Expand source code 
def start(self):
    pass

Inherited members