# -*- coding: utf-8 -*-
import codecs
import numpy as np
from obspy import UTCDateTime
from obspy.core.compatibility import from_buffer
[docs]def bcd(_i):
return (_i >> 4 & 0xF).astype(np.uint32) * 10 + (_i & 0xF)
[docs]def bcd_16bit_int(_i):
_i = bcd(_i)
return _i[::, 0] * 100 + _i[::, 1]
[docs]def bcd_hex(_i):
m = _i.shape[1]
_bcd = codecs.encode(_i.ravel(), "hex_codec").decode("ASCII").upper()
return from_buffer(_bcd, dtype="|S%d" % (m * 2))
[docs]def bcd_8bit_hex(_i):
return np.array(["{:X}".format(int(x)) for x in _i], dtype="|S2")
[docs]def bcd_julian_day_string_to_nanoseconds_of_year(_i):
timestrings = bcd_hex(_i)
return _timestrings_to_nanoseconds(timestrings)
_timegm_cache = {}
[docs]def _get_nanoseconds_for_start_of_year(year):
# Reftek 130 data format stores only the last two digits of the year.
# We currently assume that 00-49 are years 2000-2049 and 50-99 are years
# 2050-2099. We deliberately raise an exception in the read routine if the
# current year will become 2050 (just in case someone really still uses
# this code then.. ;-)
if year < 50:
year += 2000
else:
year += 1900
try:
ns = _timegm_cache[year]
except KeyError:
ns = UTCDateTime(year, 1, 1)._ns
_timegm_cache[year] = ns
return ns
[docs]def _timestrings_to_nanoseconds(timestrings):
"""
Helper routine to convert timestrings of form "DDDHHMMSSsss" to array of
integer nanosecond POSIX timestamp.
:param timestring: numpy.ndarray
:rtype: numpy.ndarray
"""
# split up the time string into tuple of
# (day of year, hours, minutes, seconds, milliseconds), still as string
nanoseconds = [(string[:3], string[3:5], string[5:7],
string[7:9], string[9:]) for string in timestrings]
nanoseconds = np.array(nanoseconds, dtype="S3").astype(np.int64)
# now scale the columns of the array, so that everything is in nanoseconds
to_nano = 1000000000
nanoseconds[:, 0] -= 1
nanoseconds[:, 0] *= 86400 * to_nano
nanoseconds[:, 1] *= 3600 * to_nano
nanoseconds[:, 2] *= 60 * to_nano
nanoseconds[:, 3] *= to_nano
nanoseconds[:, 4] *= 1000000
# sum up days, hours, minutes etc. for every row of the array
nanoseconds = nanoseconds.sum(axis=1)
return nanoseconds
[docs]def _decode_ascii(chars):
return chars.decode("ASCII")
[docs]def _parse_long_time(time_bytestring, decode=True):
"""
:returns: POSIX timestamp as integer nanoseconds
"""
if decode:
time_string = time_bytestring.decode()
else:
time_string = time_bytestring
if not time_string.strip():
return None
time_string, milliseconds = time_string[:-3], int(time_string[-3:])
t = UTCDateTime.strptime(time_string, '%Y%j%H%M%S')
nanoseconds = t._ns
nanoseconds += milliseconds * 1000000
return nanoseconds
[docs]def _16_tuple_ascii(bytestring):
item_count = 16
chars = bytestring.decode("ASCII")
if len(chars) % item_count != 0:
raise NotImplementedError("Should not happen, contact developers.")
item_size = int(len(chars) / item_count)
result = []
for i in range(item_count):
chars_ = chars[i * item_size:(i + 1) * item_size]
result.append(chars_.strip() or None)
return tuple(result)
[docs]def _16_tuple_int(bytestring):
ascii_tuple = _16_tuple_ascii(bytestring)
result = []
for chars in ascii_tuple:
if chars is None or not chars.strip():
result.append(None)
continue
result.append(int(chars))
return tuple(result)
[docs]def _16_tuple_float(bytestring):
ascii_tuple = _16_tuple_ascii(bytestring)
result = []
for chars in ascii_tuple:
if chars is None or not chars.strip():
result.append(None)
continue
result.append(float(chars))
return tuple(result)
if __name__ == '__main__':
import doctest
doctest.testmod(exclude_empty=True)