Source code for

# -*- coding: utf-8 -*-
# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright (C) 2012-2017 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
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with OpenQuake. If not, see <>.

Module :mod:`` defines :class:`Site`.
import numpy

from openquake.baselib.python3compat import range
from openquake.baselib.general import split_in_blocks
from openquake.hazardlib.geo.mesh import Mesh

[docs]class Site(object): """ Site object represents a geographical location defined by its position as well as its soil characteristics. :param location: Instance of :class:`~openquake.hazardlib.geo.point.Point` representing where the site is located. :param vs30: Average shear wave velocity in the top 30 m, in m/s. :param vs30measured: Boolean value, ``True`` if ``vs30`` was measured on that location and ``False`` if it was inferred. :param z1pt0: Vertical distance from earth surface to the layer where seismic waves start to propagate with a speed above 1.0 km/sec, in meters. :param z2pt5: Vertical distance from earth surface to the layer where seismic waves start to propagate with a speed above 2.5 km/sec, in km. :param backarc": Boolean value, ``True`` if the site is in the subduction backarc and ``False`` if it is in the subduction forearc or is unknown :raises ValueError: If any of ``vs30``, ``z1pt0`` or ``z2pt5`` is zero or negative. .. note:: :class:`Sites <Site>` are pickleable """ _slots_ = 'location vs30 vs30measured z1pt0 z2pt5 backarc'.split() def __init__(self, location, vs30, vs30measured, z1pt0, z2pt5, backarc=False): if not vs30 > 0: raise ValueError('vs30 must be positive') if not z1pt0 > 0: raise ValueError('z1pt0 must be positive') if not z2pt5 > 0: raise ValueError('z2pt5 must be positive') self.location = location self.vs30 = vs30 self.vs30measured = vs30measured self.z1pt0 = z1pt0 self.z2pt5 = z2pt5 self.backarc = backarc def __str__(self): """ >>> import openquake.hazardlib >>> loc = openquake.hazardlib.geo.point.Point(1, 2, 3) >>> str(Site(loc, 760.0, True, 100.0, 5.0)) '<Location=<Latitude=2.000000, Longitude=1.000000, Depth=3.0000>, \ Vs30=760.0000, Vs30Measured=True, Depth1.0km=100.0000, Depth2.5km=5.0000, \ Backarc=False>' """ return ( "<Location=%s, Vs30=%.4f, Vs30Measured=%r, Depth1.0km=%.4f, " "Depth2.5km=%.4f, Backarc=%r>") % ( self.location, self.vs30, self.vs30measured, self.z1pt0, self.z2pt5, self.backarc) def __hash__(self): return hash((self.location.x, self.location.y)) def __eq__(self, other): return (self.location.x, self.location.y) == ( other.location.x, other.location.y) def __repr__(self): """ >>> import openquake.hazardlib >>> loc = openquake.hazardlib.geo.point.Point(1, 2, 3) >>> site = Site(loc, 760.0, True, 100.0, 5.0) >>> str(site) == repr(site) True """ return self.__str__()
def _extract(array_or_float, indices): try: # if array return array_or_float[indices] except TypeError: # if float return array_or_float
[docs]class SiteCollection(object): """ A collection of :class:`sites <Site>`. Instances of this class are intended to represent a large collection of sites in a most efficient way in terms of memory usage. .. note:: If a :class:`SiteCollection` is created from sites containing only lon and lat, iterating over the collection will yield :class:`Sites <Site>` with a reference depth of 0.0 (the sea level). Otherwise, it is possible to model the sites on a realistic topographic surface by specifying the `depth` of each site. :param sites: A list of instances of :class:`Site` class. """ dtype = numpy.dtype([ ('sids', numpy.uint32), ('lons', numpy.float64), ('lats', numpy.float64), ('depths', numpy.float64), ('vs30', numpy.float64), ('vs30measured', numpy.bool), ('z1pt0', numpy.float64), ('z2pt5', numpy.float64), ('backarc', numpy.bool), ])
[docs] @classmethod def from_points(cls, lons, lats, depths, sitemodel): """ Build the site collection from :param lons: a sequence of longitudes :param lats: a sequence of latitudes :param depths: a sequence of depths :param sitemodel: an object containing the attributes reference_vs30_value, reference_vs30_type, reference_depth_to_1pt0km_per_sec, reference_depth_to_2pt5km_per_sec, reference_backarc """ if depths is None: depths = numpy.zeros(len(lons)) assert len(lons) == len(lats) == len(depths), (len(lons), len(lats), len(depths)) self = object.__new__(cls) self.indices = None self.array = arr = numpy.zeros(len(lons), self.dtype) arr['sids'] = numpy.arange(len(lons), dtype=numpy.uint32) arr['lons'] = numpy.array(lons) arr['lats'] = numpy.array(lats) arr['depths'] = numpy.array(depths) arr['vs30'] = sitemodel.reference_vs30_value arr['vs30measured'] = sitemodel.reference_vs30_type == 'measured' arr['z1pt0'] = sitemodel.reference_depth_to_1pt0km_per_sec arr['z2pt5'] = sitemodel.reference_depth_to_2pt5km_per_sec arr['backarc'] = sitemodel.reference_backarc arr.flags.writeable = False return self
[docs] @classmethod def filtered(cls, indices, array): """ :returns: a filtered SiteCollection instance """ self = object.__new__(cls) self.indices = indices self.array = array return self
def __init__(self, sites): """ Build a complete SiteCollection from a list of Site objects """ self.indices = None if hasattr(sites, 'sids'): numpy.testing.assert_equal(sites.sids, numpy.arange(len(sites))) self.array = arr = numpy.zeros(len(sites), self.dtype) for i in range(len(arr)): arr['sids'][i] = i arr['lons'][i] = sites[i].location.longitude arr['lats'][i] = sites[i].location.latitude arr['depths'][i] = sites[i].location.depth arr['vs30'][i] = sites[i].vs30 arr['vs30measured'][i] = sites[i].vs30measured arr['z1pt0'][i] = sites[i].z1pt0 arr['z2pt5'][i] = sites[i].z2pt5 arr['backarc'][i] = sites[i].backarc # protect arrays from being accidentally changed. it is useful # because we pass these arrays directly to a GMPE through # a SiteContext object and if a GMPE is implemented poorly it could # modify the site values, thereby corrupting site and all the # subsequent calculation. note that this doesn't protect arrays from # being changed by calling itemset() arr.flags.writeable = False def __eq__(self, other): arr = self.array == other.array if isinstance(arr, numpy.ndarray): return arr.all() return arr def __ne__(self, other): return not self.__eq__(other) def __toh5__(self): return (self.array, dict(indices=self.indices) if self.indices is not None else {}) def __fromh5__(self, array, attrs): self.indices = attrs.get('indices') self.array = array @property def mesh(self): """Return a mesh with the given lons, lats, and depths""" return Mesh(self.lons, self.lats, self.depths) @property def complete(self): """Return a complete SiteCollection object""" if self.indices is None: return self new = object.__new__(self.__class__) new.indices = None new.array = self.array return new
[docs] def at_sea_level(self): """True if all depths are zero""" return (self.depths == 0).all()
[docs] def split_in_tiles(self, hint): """ Split a SiteCollection into a set of tiles (SiteCollection instances). :param hint: hint for how many tiles to generate """ tiles = [] for seq in split_in_blocks(range(len(self)), hint or 1): sc = SiteCollection.__new__(SiteCollection) sc.indices = None sc.array = self.array[numpy.array(seq, int)] tiles.append(sc) return tiles
def __iter__(self): """ Iterate through all :class:`sites <Site>` in the collection, yielding one at a time. """ for i, location in enumerate(self.mesh): yield Site(location, self.vs30[i], self.vs30measured[i], self.z1pt0[i], self.z2pt5[i], self.backarc[i])
[docs] def filter(self, mask): """ Create a SiteCollection with only a subset of sites. :param mask: Numpy array of boolean values of the same length as the site collection. ``True`` values should indicate that site with that index should be included into the filtered collection. :returns: A new :class:`SiteCollection` instance, unless all the values in ``mask`` are ``True``, in which case this site collection is returned, or if all the values in ``mask`` are ``False``, in which case method returns ``None``. New collection has data of only those sites that were marked for inclusion in the mask. """ assert len(mask) == len(self), (len(mask), len(self)) if mask.all(): # all sites satisfy the filter, return # this collection unchanged return self if not mask.any(): # no sites pass the filter, return None return None # extract indices of Trues from the mask if self.indices is None: indices = mask.nonzero()[0] else: indices = self.indices.take(mask.nonzero()[0]) return SiteCollection.filtered(indices, self.array)
def __getstate__(self): return dict(array=self.array, indices=self.indices) def __getattr__(self, name): if name not in ('vs30 vs30measured z1pt0 z2pt5 backarc lons lats ' 'depths sids'): raise AttributeError(name) if self.indices is None: idx = slice(None) else: idx = self.indices return self.array[idx][name] def __len__(self): """ Return the number of sites in the collection. """ return (len(self.indices) if self.indices is not None else len(self.array)) def __repr__(self): total_sites = len(self.array) return '<SiteCollection with %d/%d sites>' % (len(self), total_sites)