Source code for openquake.hazardlib.mfd.arbitrary_mfd

# The Hazard Library
# Copyright (C) 2016 GEM Foundation
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""
Module :mod:`openquake.hazardlib.mfd.evenly_discretized` defines an evenly
discretized MFD.
"""
from openquake.hazardlib.mfd.base import BaseMFD
from openquake.baselib.slots import with_slots


@with_slots
[docs]class ArbitraryMFD(BaseMFD): """ An arbitrary MFD is defined as a list of tuples of magnitude values and their corresponding rates :param magnitudes: List of magnitudes :param occurrence_rates: The list of non-negative float values representing the actual annual occurrence rates. The resulting histogram has as many bins as this list length. """ MODIFICATIONS = set(('set_mfd',)) _slots_ = 'magnitudes occurrence_rates'.split() def __init__(self, magnitudes, occurrence_rates): self.magnitudes = magnitudes self.occurrence_rates = occurrence_rates self.check_constraints()
[docs] def check_constraints(self): """ Checks the following constraints: * Magnitude list and occurrence rate lists are the same length * Occurrence rates list is not empty. * Each number in occurrence rates list is non-negative. * Minimum magnitude is positive. """ if not self.occurrence_rates: raise ValueError('at least one bin must be specified') if not all(value >= 0 for value in self.occurrence_rates): raise ValueError('all occurrence rates must not be negative') if not any(value > 0 for value in self.occurrence_rates): raise ValueError('at least one occurrence rate must be positive') if not len(self.magnitudes) == len(self.occurrence_rates): raise ValueError( 'lists of magnitudes and rates must have same length')
[docs] def get_annual_occurrence_rates(self): """ Returns the predefined annual occurrence rates. """ return list(zip(self.magnitudes, self.occurrence_rates))
[docs] def get_min_max_mag(self): """ Returns the minumun and maximum magnitudes """ return min(self.magnitudes), max(self.magnitudes)
[docs] def modify_set_mfd(self, magnitudes, occurrence_rates): """ Applies absolute modification of the MFD from the ``magnitudes``, ``occurrence_rates`` modification. :param magnitudes: List of magnitudes :param occurrence_rates: The list of non-negative float values representing the actual annual occurrence rates. The resulting histogram has as many bins as this list length. """ self.magnitudes = magnitudes self.occurrence_rates = occurrence_rates self.check_constraints()