Source code for openquake.hazardlib.calc.hazard_curve

# coding: utf-8
# The Hazard Library
# Copyright (C) 2012-2014, 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/>.
"""
:mod:`openquake.hazardlib.calc.hazard_curve` implements
:func:`hazard_curves`.
"""
import sys
import time
import collections

import numpy

from openquake.baselib.python3compat import range, raise_
from openquake.baselib.performance import DummyMonitor
from openquake.hazardlib.calc import filters
from openquake.hazardlib.gsim.base import ContextMaker, FarAwayRupture
from openquake.hazardlib.imt import from_string
from openquake.baselib.general import deprecated


[docs]def zero_curves(num_sites, imtls): """ :param num_sites: the number of sites :param imtls: the intensity measure levels dictionary :returns: an array of zero curves with length num_sites """ # numpy dtype for the hazard curves imt_dt = numpy.dtype([(imt, float, 1 if imls is None else len(imls)) for imt, imls in imtls.items()]) zero = numpy.zeros(num_sites, imt_dt) return zero
[docs]def zero_maps(num_sites, imts): """ :param num_sites: the number of sites :param imts: the intensity measure types :returns: an array of zero curves with length num_sites """ # numpy dtype for the hazard maps imt_dt = numpy.dtype([(imt, float) for imt in imts]) zero = numpy.zeros(num_sites, imt_dt) return zero
[docs]def agg_curves(acc, curves): """ Aggregate hazard curves by composing the probabilities. :param acc: an accumulator array :param curves: an array of hazard curves :returns: a new accumulator """ new = numpy.array(acc) # copy of the accumulator for imt in curves.dtype.fields: new[imt] = 1. - (1. - curves[imt]) * (1. - acc[imt]) return new
@deprecated('Use calc_hazard_curves instead')
[docs]def hazard_curves( sources, sites, imtls, gsim_by_trt, truncation_level=None, source_site_filter=filters.source_site_noop_filter, rupture_site_filter=filters.rupture_site_noop_filter): """ Deprecated. It does the same job of :func:`openquake.hazardlib.calc.hazard_curve.calc_hazard_curves`, with the only difference that the intensity measure types in input and output are hazardlib objects instead of simple strings. """ imtls = {str(imt): imls for imt, imls in imtls.items()} curves_by_imt = calc_hazard_curves( sources, sites, imtls, gsim_by_trt, truncation_level, source_site_filter=filters.source_site_noop_filter, rupture_site_filter=filters.rupture_site_noop_filter) return {from_string(imt): curves_by_imt[imt] for imt in imtls}
[docs]def calc_hazard_curves( sources, sites, imtls, gsim_by_trt, truncation_level=None, source_site_filter=filters.source_site_noop_filter, rupture_site_filter=filters.rupture_site_noop_filter, maximum_distance=None): """ Compute hazard curves on a list of sites, given a set of seismic sources and a set of ground shaking intensity models (one per tectonic region type considered in the seismic sources). Probability of ground motion exceedance is computed using the following formula :: P(X≥x|T) = 1 - ∏ ∏ Prup_ij(X<x|T) where ``P(X≥x|T)`` is the probability that the ground motion parameter ``X`` is exceeding level ``x`` one or more times in a time span ``T``, and ``Prup_ij(X<x|T)`` is the probability that the j-th rupture of the i-th source is not producing any ground motion exceedance in time span ``T``. The first product ``∏`` is done over sources, while the second one is done over ruptures in a source. The above formula computes the probability of having at least one ground motion exceedance in a time span as 1 minus the probability that none of the ruptures in none of the sources is causing a ground motion exceedance in the same time span. The basic assumption is that seismic sources are independent, and ruptures in a seismic source are also independent. :param sources: A sequence of seismic sources objects (instances of subclasses of :class:`~openquake.hazardlib.source.base.BaseSeismicSource`). :param sites: Instance of :class:`~openquake.hazardlib.site.SiteCollection` object, representing sites of interest. :param imtls: Dictionary mapping intensity measure type strings to lists of intensity measure levels. :param gsim_by_trt: Dictionary mapping tectonic region types (members of :class:`openquake.hazardlib.const.TRT`) to :class:`~openquake.hazardlib.gsim.base.GMPE` or :class:`~openquake.hazardlib.gsim.base.IPE` objects. :param truncation_level: Float, number of standard deviations for truncation of the intensity distribution. :param source_site_filter: Optional source-site filter function. See :mod:`openquake.hazardlib.calc.filters`. :param rupture_site_filter: Optional rupture-site filter function. See :mod:`openquake.hazardlib.calc.filters`. :returns: An array of size N, where N is the number of sites, which elements are records with fields given by the intensity measure types; the size of each field is given by the number of levels in ``imtls``. """ sources_by_trt = collections.defaultdict(list) for src in sources: sources_by_trt[src.tectonic_region_type].append(src) curves = zero_curves(len(sites), imtls) for trt in sources_by_trt: curves = agg_curves(curves, hazard_curves_per_trt( sources_by_trt[trt], sites, imtls, [gsim_by_trt[trt]], truncation_level, source_site_filter, rupture_site_filter)[0]) return curves
# TODO: remove the rupture_site_filter, since its work is now done by the # maximum_distance parameter; see what would break
[docs]def hazard_curves_per_trt( sources, sites, imtls, gsims, truncation_level=None, source_site_filter=filters.source_site_noop_filter, rupture_site_filter=filters.rupture_site_noop_filter, maximum_distance=None, monitor=DummyMonitor()): """ Compute the hazard curves for a set of sources belonging to the same tectonic region type for all the GSIMs associated to that TRT. The arguments are the same as in :func:`calc_hazard_curves`, except for ``gsims``, which is a list of GSIM instances. :returns: A list of G arrays of size N, where N is the number of sites and G the number of gsims. Each array contains records with fields given by the intensity measure types; the size of each field is given by the number of levels in ``imtls``. """ cmaker = ContextMaker(gsims, maximum_distance) gnames = list(map(str, gsims)) imt_dt = numpy.dtype([(imt, float, len(imtls[imt])) for imt in sorted(imtls)]) imts = {from_string(imt): imls for imt, imls in imtls.items()} curves = [numpy.ones(len(sites), imt_dt) for gname in gnames] sources_sites = ((source, sites) for source in sources) ctx_mon = monitor('making contexts', measuremem=False) rup_mon = monitor('getting ruptures', measuremem=False) pne_mon = monitor('computing poes', measuremem=False) monitor.calc_times = [] # pairs (src_id, delta_t) for source, s_sites in source_site_filter(sources_sites): t0 = time.time() try: with rup_mon: rupture_sites = list(rupture_site_filter( (rupture, s_sites) for rupture in source.iter_ruptures())) for rupture, r_sites in rupture_sites: with ctx_mon: try: sctx, rctx, dctx = cmaker.make_contexts( r_sites, rupture) except FarAwayRupture: continue for i, gsim in enumerate(gsims): with pne_mon: for imt in imts: poes = gsim.get_poes( sctx, rctx, dctx, imt, imts[imt], truncation_level) pno = rupture.get_probability_no_exceedance(poes) expanded_pno = sctx.sites.expand(pno, 1.0) curves[i][str(imt)] *= expanded_pno except Exception as err: etype, err, tb = sys.exc_info() msg = 'An error occurred with source id=%s. Error: %s' msg %= (source.source_id, str(err)) raise_(etype, msg, tb) # we are attaching the calculation times to the monitor # so that oq-lite (and the engine) can store them monitor.calc_times.append((source.id, time.time() - t0)) # NB: source.id is an integer; it should not be confused # with source.source_id, which is a string for i in range(len(gnames)): for imt in imtls: curves[i][imt] = 1. - curves[i][imt] return curves