# http://pyrocko.org - GPLv3
#
# The Pyrocko Developers, 21st Century
# ---|P------/S----------~Lg----------
'''
Functionality to handle tiled global topography datasets.
'''
import math
import logging
import os.path as op
import numpy as num
from . import tile
from ..util import get_download_callback
from pyrocko import util
try:
range = xrange
except NameError:
pass
logger = logging.getLogger('pyrocko.dataset.topo.dataset')
[docs]class TiledGlobalDataset(object):
'''
Tiled global dataset.
'''
def __init__(self, name, nx, ny, ntx, nty, dtype, data_dir=None,
citation=None, region=None):
# dataset geometry (including overlap/endpoints)
self.nx = int(nx)
self.ny = int(ny)
self.xmin = -180.
self.xmax = 180.
self.ymin = -90.
self.ymax = 90.
self.dx = (self.xmax-self.xmin) / (self.nx - 1)
self.dy = (self.ymax-self.ymin) / (self.ny - 1)
# tile geometry (including overlap)
self.ntx = int(ntx)
self.nty = int(nty)
self.stx = (self.ntx - 1) * self.dx
self.sty = (self.nty - 1) * self.dy
self.ntilesx = (self.nx - 1) // (self.ntx - 1)
self.ntilesy = (self.ny - 1) // (self.nty - 1)
self.name = name
self.dtype = dtype
self.data_dir = data_dir
self.citation = citation
if region is not None:
self.region = self.positive_region(region)
else:
self.region = None
def covers(self, region):
if self.region is None:
return True
a = self.region
b = self.positive_region(region)
return ((
(a[0] <= b[0] and b[1] <= b[1]) or
(a[0] <= b[0]+360. and b[1]+360 <= a[1]))
and a[2] <= b[2] and b[3] <= a[3])
def is_suitable(self, region, dmin, dmax):
d = 360. / (self.nx - 1)
return self.covers(region) and dmin <= d <= dmax
def download_file(self, url, fpath, username=None, password=None):
# TODO: Add logstring
util.download_file(
url, fpath, username, password,
status_callback=get_download_callback(
'Downloading %s topography...' % self.__class__.__name__))
def x(self):
return self.xmin + num.arange(self.nx) * self.dx
def y(self):
return self.ymin + num.arange(self.ny) * self.dy
def positive_region(self, region):
xmin, xmax, ymin, ymax = [float(x) for x in region]
assert -180. - 360. <= xmin < 180.
assert -180. < xmax <= 180. + 360.
assert -90. <= ymin < 90.
assert -90. < ymax <= 90.
if xmax < xmin:
xmax += 360.
if xmin < -180.:
xmin += 360.
xmax += 360.
return (xmin, xmax, ymin, ymax)
def tile_indices(self, region):
xmin, xmax, ymin, ymax = self.positive_region(region)
itxmin = int(math.floor((xmin - self.xmin) / self.stx))
itxmax = int(math.ceil((xmax - self.xmin) / self.stx))
if itxmin == itxmax:
itxmax += 1
itymin = int(math.floor((ymin - self.ymin) / self.sty))
itymax = int(math.ceil((ymax - self.ymin) / self.sty))
if itymin == itymax:
if itymax != self.ntilesy:
itymax += 1
else:
itymin -= 1
indices = []
for ity in range(itymin, itymax):
for itx in range(itxmin, itxmax):
indices.append((itx % self.ntilesx, ity))
return indices
def get_tile(self, itx, ity):
return None
def get(self, region):
if len(region) == 2:
x, y = region
t = self.get((x, x, y, y))
if t is not None:
return t.get(x, y)
else:
return None
indices = self.tile_indices(region)
tiles = []
for itx, ity in indices:
t = self.get_tile(itx, ity)
if t:
tiles.append(t)
return tile.combine(tiles, region)
def get_with_repeat(self, region):
xmin, xmax, ymin, ymax = region
ymin2 = max(-90., ymin)
ymax2 = min(90., ymax)
region2 = xmin, xmax, ymin2, ymax2
t = self.get(region2)
if t is not None and region2 != region:
t.yextend_with_repeat(ymin, ymax)
return t
[docs]class DecimatedTiledGlobalDataset(TiledGlobalDataset):
'''
Decimated variant of a tiled global dataset.
'''
def __init__(self, name, base, ndeci, data_dir=None, ntx=None, nty=None):
assert ndeci % 2 == 0
assert (base.nx - 1) % ndeci == 0
assert (base.ny - 1) % ndeci == 0
nx = (base.nx - 1) // ndeci + 1
ny = (base.ny - 1) // ndeci + 1
if ntx is None:
ntx = base.ntx
if nty is None:
nty = base.nty
assert (nx - 1) % (ntx - 1) == 0
assert (ny - 1) % (nty - 1) == 0
if data_dir is None:
data_dir = op.join(base.data_dir, 'decimated_%i' % ndeci)
TiledGlobalDataset.__init__(self, name, nx, ny, ntx, nty, base.dtype,
data_dir=data_dir, citation=base.citation,
region=base.region)
self.base = base
self.ndeci = ndeci
def make_tile(self, itx, ity, fpath):
nh = self.ndeci // 2
xmin = self.xmin + itx*self.stx - self.base.dx * nh
xmax = self.xmin + (itx+1)*self.stx + self.base.dx * nh
ymin = self.ymin + ity*self.sty - self.base.dy * nh
ymax = self.ymin + (ity+1)*self.sty + self.base.dy * nh
t = self.base.get_with_repeat((xmin, xmax, ymin, ymax))
if t is not None:
t.decimate(self.ndeci)
util.ensuredirs(fpath)
with open(fpath, 'w') as f:
if t is not None:
t.data.tofile(f)
def make_if_needed(self, itx, ity):
assert 0 <= itx < self.ntilesx
assert 0 <= ity < self.ntilesy
fn = '%02i.%02i.bin' % (ity, itx)
fpath = op.join(self.data_dir, fn)
if not op.exists(fpath):
logger.info('making decimated tile: %s (%s)' % (fn, self.name))
self.make_tile(itx, ity, fpath)
def get_tile(self, itx, ity):
assert 0 <= itx < self.ntilesx
assert 0 <= ity < self.ntilesy
self.make_if_needed(itx, ity)
fn = '%02i.%02i.bin' % (ity, itx)
fpath = op.join(self.data_dir, fn)
with open(fpath, 'r') as f:
data = num.fromfile(f, dtype=self.dtype)
if data.size == 0:
return None
assert data.size == self.ntx*self.nty
data = data.reshape((self.ntx, self.nty))
return tile.Tile(
self.xmin + itx*self.stx,
self.ymin + ity*self.sty,
self.dx, self.dx, data)
def make_all_missing(self):
for ity in range(self.ntilesy):
for itx in range(self.ntilesx):
self.make_if_needed(itx, ity)
