Source code for openquake.commonlib.calc

# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
#
# Copyright (C) 2014-2017 GEM Foundation
#
# OpenQuake 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.
#
# OpenQuake 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.
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# You should have received a copy of the GNU Affero General Public License
# along with OpenQuake. If not, see <http://www.gnu.org/licenses/>.

from __future__ import division
import warnings
import numpy
import h5py

from openquake.baselib import hdf5
from openquake.baselib.python3compat import decode
from openquake.hazardlib.geo.mesh import surface_to_mesh, point3d
from openquake.hazardlib.gsim.base import ContextMaker
from openquake.hazardlib.imt import from_string
from openquake.hazardlib import calc, probability_map

TWO16 = 2 ** 16
MAX_INT = 2 ** 31 - 1  # this is used in the random number generator
# in this way even on 32 bit machines Python will not have to convert
# the generated seed into a long integer

U8 = numpy.uint8
U16 = numpy.uint16
I32 = numpy.int32
U32 = numpy.uint32
F32 = numpy.float32
U64 = numpy.uint64
F64 = numpy.float64

EVENTS = -2
NBYTES = -1
event_dt = numpy.dtype([('eid', U64), ('grp_id', U16), ('ses', U32),
                        ('sample', U32)])

# ############## utilities for the classical calculator ############### #


[docs]def convert_to_array(pmap, nsites, imtls): """ Convert the probability map into a composite array with header of the form PGA-0.1, PGA-0.2 ... :param pmap: probability map :param nsites: total number of sites :param imtls: a DictArray with IMT and levels :returns: a composite array of lenght nsites """ lst = [] # build the export dtype, of the form PGA-0.1, PGA-0.2 ... for imt, imls in imtls.items(): for iml in imls: lst.append(('%s-%s' % (imt, iml), numpy.float64)) curves = numpy.zeros(nsites, numpy.dtype(lst)) for sid, pcurve in pmap.items(): curve = curves[sid] idx = 0 for imt, imls in imtls.items(): for iml in imls: curve['%s-%s' % (imt, iml)] = pcurve.array[idx] idx += 1 return curves
# ######################### hazard maps ################################### # # cutoff value for the poe EPSILON = 1E-30
[docs]def compute_hazard_maps(curves, imls, poes): """ Given a set of hazard curve poes, interpolate a hazard map at the specified ``poe``. :param curves: 2D array of floats. Each row represents a curve, where the values in the row are the PoEs (Probabilities of Exceedance) corresponding to ``imls``. Each curve corresponds to a geographical location. :param imls: Intensity Measure Levels associated with these hazard ``curves``. Type should be an array-like of floats. :param poes: Value(s) on which to interpolate a hazard map from the input ``curves``. Can be an array-like or scalar value (for a single PoE). :returns: An array of shape N x P, where N is the number of curves and P the number of poes. """ poes = numpy.array(poes) if len(poes.shape) == 0: # `poes` was passed in as a scalar; # convert it to 1D array of 1 element poes = poes.reshape(1) if len(curves.shape) == 1: # `curves` was passed as 1 dimensional array, there is a single site curves = curves.reshape((1,) + curves.shape) # 1 x L L = curves.shape[1] # number of levels if L != len(imls): raise ValueError('The curves have %d levels, %d were passed' % (L, len(imls))) result = [] with warnings.catch_warnings(): warnings.simplefilter("ignore") # avoid RuntimeWarning: divide by zero encountered in log # happening in the classical_tiling tests imls = numpy.log(numpy.array(imls[::-1])) for curve in curves: # the hazard curve, having replaced the too small poes with EPSILON curve_cutoff = [max(poe, EPSILON) for poe in curve[::-1]] hmap_val = [] for poe in poes: # special case when the interpolation poe is bigger than the # maximum, i.e the iml must be smaller than the minumum if poe > curve_cutoff[-1]: # the greatest poes in the curve # extrapolate the iml to zero as per # https://bugs.launchpad.net/oq-engine/+bug/1292093 # a consequence is that if all poes are zero any poe > 0 # is big and the hmap goes automatically to zero hmap_val.append(0) else: # exp-log interpolation, to reduce numerical errors # see https://bugs.launchpad.net/oq-engine/+bug/1252770 val = numpy.exp( numpy.interp( numpy.log(poe), numpy.log(curve_cutoff), imls)) hmap_val.append(val) result.append(hmap_val) return numpy.array(result)
# ######################### GMF->curves #################################### # # NB (MS): the approach used here will not work for non-poissonian models def _gmvs_to_haz_curve(gmvs, imls, invest_time, duration): """ Given a set of ground motion values (``gmvs``) and intensity measure levels (``imls``), compute hazard curve probabilities of exceedance. :param gmvs: A list of ground motion values, as floats. :param imls: A list of intensity measure levels, as floats. :param float invest_time: Investigation time, in years. It is with this time span that we compute probabilities of exceedance. Another way to put it is the following. When computing a hazard curve, we want to answer the question: What is the probability of ground motion meeting or exceeding the specified levels (``imls``) in a given time span (``invest_time``). :param float duration: Time window during which GMFs occur. Another was to say it is, the period of time over which we simulate ground motion occurrences. NOTE: Duration is computed as the calculation investigation time multiplied by the number of stochastic event sets. :returns: Numpy array of PoEs (probabilities of exceedance). """ # convert to numpy array and redimension so that it can be broadcast with # the gmvs for computing PoE values; there is a gmv for each rupture # here is an example: imls = [0.03, 0.04, 0.05], gmvs=[0.04750576] # => num_exceeding = [1, 1, 0] coming from 0.04750576 > [0.03, 0.04, 0.05] imls = numpy.array(imls).reshape((len(imls), 1)) num_exceeding = numpy.sum(numpy.array(gmvs) >= imls, axis=1) poes = 1 - numpy.exp(- (invest_time / duration) * num_exceeding) return poes # ################## utilities for classical calculators ################ #
[docs]def get_imts_periods(imtls): """ Returns a list of IMT strings and a list of periods. There is an element for each IMT of type Spectral Acceleration, including PGA which is considered an alias for SA(0.0). The lists are sorted by period. :param imtls: a set of intensity measure type strings :returns: a list of IMT strings and a list of periods """ def getperiod(imt): return imt[1] or 0 imts = sorted((from_string(imt) for imt in imtls if imt.startswith('SA') or imt == 'PGA'), key=getperiod) return [str(imt) for imt in imts], [imt[1] or 0.0 for imt in imts]
[docs]def make_hmap(pmap, imtls, poes): """ Compute the hazard maps associated to the passed probability map. :param pmap: hazard curves in the form of a ProbabilityMap :param imtls: DictArray with M intensity measure types :param poes: P PoEs where to compute the maps :returns: a ProbabilityMap with size (N, M * P, 1) """ M, P = len(imtls), len(poes) hmap = probability_map.ProbabilityMap.build(M * P, 1, pmap) if len(pmap) == 0: return hmap # empty hazard map for i, imt in enumerate(imtls): curves = numpy.array([pmap[sid].array[imtls.slicedic[imt], 0] for sid in pmap.sids]) data = compute_hazard_maps(curves, imtls[imt], poes) # array N x P for sid, value in zip(pmap.sids, data): array = hmap[sid].array for j, val in enumerate(value): array[i * P + j] = val return hmap
[docs]def make_uhs(pmap, imtls, poes, nsites): """ Make Uniform Hazard Spectra curves for each location. It is assumed that the `lons` and `lats` for each of the `maps` are uniform. :param pmap: a probability map of hazard curves :param imtls: a dictionary of intensity measure types and levels :param poes: a sequence of PoEs for the underlying hazard maps :returns: an composite array containing nsites uniform hazard maps """ P = len(poes) imts, _ = get_imts_periods(imtls) hmap = make_hmap(pmap, imtls, poes) for sid in range(nsites): # fill empty positions if any hmap.setdefault(sid, 0) array = hmap.array imts_dt = numpy.dtype([(str(imt), F64) for imt in imts]) uhs_dt = numpy.dtype([(str(poe), imts_dt) for poe in poes]) uhs = numpy.zeros(nsites, uhs_dt) for j, poe in enumerate(map(str, poes)): for i, imt in enumerate(imtls): if imt in imts: uhs[poe][imt] = array[:, i * P + j, 0] return uhs
[docs]def fix_minimum_intensity(min_iml, imts): """ :param min_iml: a dictionary, possibly with a 'default' key :param imts: an ordered list of IMTs :returns: a numpy array of intensities, one per IMT Make sure the dictionary minimum_intensity (provided by the user in the job.ini file) is filled for all intensity measure types and has no key named 'default'. Here is how it works: >>> min_iml = {'PGA': 0.1, 'default': 0.05} >>> fix_minimum_intensity(min_iml, ['PGA', 'PGV']) array([ 0.1 , 0.05], dtype=float32) >>> sorted(min_iml.items()) [('PGA', 0.1), ('PGV', 0.05)] """ if min_iml: for imt in imts: try: min_iml[imt] = calc.filters.getdefault(min_iml, imt) except KeyError: raise ValueError( 'The parameter `minimum_intensity` in the job.ini ' 'file is missing the IMT %r' % imt) if 'default' in min_iml: del min_iml['default'] return F32([min_iml.get(imt, 0) for imt in imts])
[docs]def check_overflow(calc): """ :param calc: an event based calculator Raise a ValueError if the number of sites is larger than 65,536 or the number of IMTs is larger than 256 or the number of ruptures is larger than 4,294,967,296. The limits are due to the numpy dtype used to store the GMFs (gmv_dt). They could be relaxed in the future. """ max_ = dict(sites=2**16, events=2**32, imts=2**8) num_ = dict(sites=len(calc.sitecol), events=len(calc.datastore['events']), imts=len(calc.oqparam.imtls)) for var in max_: if num_[var] > max_[var]: raise ValueError( 'The event based calculator is restricted to ' '%d %s, got %d' % (max_[var], var, num_[var]))
[docs]class RuptureData(object): """ Container for information about the ruptures of a given tectonic region type. """ def __init__(self, trt, gsims): self.trt = trt self.cmaker = ContextMaker(gsims) self.params = sorted(self.cmaker.REQUIRES_RUPTURE_PARAMETERS - set('mag strike dip rake hypo_depth'.split())) self.dt = numpy.dtype([ ('rup_id', U32), ('multiplicity', U16), ('eidx', U32), ('occurrence_rate', F64), ('mag', F32), ('lon', F32), ('lat', F32), ('depth', F32), ('strike', F32), ('dip', F32), ('rake', F32), ('boundary', hdf5.vstr)] + [(param, F32) for param in self.params])
[docs] def to_array(self, ebruptures): """ Convert a list of ebruptures into an array of dtype RuptureRata.dt """ data = [] for ebr in ebruptures: rup = ebr.rupture rc = self.cmaker.make_rupture_context(rup) ruptparams = tuple(getattr(rc, param) for param in self.params) point = rup.surface.get_middle_point() multi_lons, multi_lats = rup.surface.get_surface_boundaries() bounds = ','.join('((%s))' % ','.join( '%.5f %.5f' % (lon, lat) for lon, lat in zip(lons, lats)) for lons, lats in zip(multi_lons, multi_lats)) try: rate = ebr.rupture.occurrence_rate except AttributeError: # for nonparametric sources rate = numpy.nan data.append( (ebr.serial, ebr.multiplicity, ebr.eidx1, rate, rup.mag, point.x, point.y, point.z, rup.surface.get_strike(), rup.surface.get_dip(), rup.rake, 'MULTIPOLYGON(%s)' % decode(bounds)) + ruptparams) return numpy.array(data, self.dt)
[docs]class RuptureSerializer(object): """ Serialize event based ruptures on an HDF5 files. Populate the datasets `ruptures` and `sids`. """ rupture_dt = numpy.dtype([ ('serial', U32), ('grp_id', U16), ('code', U8), ('eidx1', U32), ('eidx2', U32), ('pmfx', I32), ('seed', U32), ('mag', F32), ('rake', F32), ('occurrence_rate', F32), ('hypo', point3d), ('sx', U16), ('sy', U8), ('sz', U16), ('points', h5py.special_dtype(vlen=point3d)), ]) pmfs_dt = numpy.dtype([ ('serial', U32), ('pmf', h5py.special_dtype(vlen=F32)), ])
[docs] @classmethod def get_array_nbytes(cls, ebruptures): """ Convert a list of EBRuptures into a numpy composite array """ lst = [] nbytes = 0 for ebrupture in ebruptures: rup = ebrupture.rupture mesh = surface_to_mesh(rup.surface) sx, sy, sz = mesh.shape points = mesh.flatten() # sanity checks assert sx < TWO16, 'Too many multisurfaces: %d' % sx assert sy < 256, 'The rupture mesh spacing is too small' assert sz < TWO16, 'The rupture mesh spacing is too small' hypo = rup.hypocenter.x, rup.hypocenter.y, rup.hypocenter.z rate = getattr(rup, 'occurrence_rate', numpy.nan) tup = (ebrupture.serial, ebrupture.grp_id, rup.code, ebrupture.eidx1, ebrupture.eidx2, getattr(ebrupture, 'pmfx', -1), rup.seed, rup.mag, rup.rake, rate, hypo, sx, sy, sz, points) lst.append(tup) nbytes += cls.rupture_dt.itemsize + mesh.nbytes return numpy.array(lst, cls.rupture_dt), nbytes
def __init__(self, datastore): self.datastore = datastore self.nbytes = 0
[docs] def save(self, ebruptures, eidx=0): """ Populate a dictionary of site IDs tuples and save the ruptures. :param ebruptures: a list of EBRupture objects to save :param eidx: the last event index saved """ pmfbytes = 0 for ebr in ebruptures: mul = ebr.multiplicity ebr.eidx1 = eidx ebr.eidx2 = eidx + mul eidx += mul rup = ebr.rupture if hasattr(rup, 'pmf'): pmfs = numpy.array([(ebr.serial, rup.pmf)], self.pmfs_dt) dset = self.datastore.extend('pmfs', pmfs) ebr.pmfx = len(dset) - 1 pmfbytes += self.pmfs_dt.itemsize + rup.pmf.nbytes # store the ruptures in a compact format array, nbytes = self.get_array_nbytes(ebruptures) key = 'ruptures' try: dset = self.datastore.getitem(key) except KeyError: # not created yet previous = 0 else: previous = dset.attrs['nbytes'] self.datastore.extend(key, array, nbytes=previous + nbytes) # save nbytes occupied by the PMFs if pmfbytes: if 'nbytes' in dset.attrs: dset.attrs['nbytes'] += pmfbytes else: dset.attrs['nbytes'] = pmfbytes self.datastore.flush()
[docs] def close(self): pass