def readSU(filename, headonly=False, byteorder=None,
unpack_trace_headers=False, **kwargs): # @UnusedVariable
"""
Reads a Seismic Unix (SU) file and returns an ObsPy Stream object.
.. warning::
This function should NOT be called directly, it registers via the
ObsPy :func:`~obspy.core.stream.read` function, call this instead.
:type filename: str
:param filename: SU file to be read.
:type headonly: bool, optional
:param headonly: If set to True, read only the header and omit the waveform
data.
:type byteorder: str or ``None``
:param byteorder: Determines the endianness of the file. Either ``'>'`` for
big endian or ``'<'`` for little endian. If it is ``None``, it will try
to autodetect the endianness. The endianness is always valid for the
whole file. Defaults to ``None``.
:type unpack_trace_headers: bool, optional
:param unpack_trace_headers: Determines whether or not all trace header
values will be unpacked during reading. If ``False`` it will greatly
enhance performance and especially memory usage with large files. The
header values can still be accessed and will be calculated on the fly
but tab completion will no longer work. Look in the headers.py for a
list of all possible trace header values. Defaults to ``False``.
:returns: A ObsPy :class:`~obspy.core.stream.Stream` object.
.. rubric:: Example
>>> from obspy import read
>>> st = read("/path/to/1.su_first_trace")
>>> st #doctest: +ELLIPSIS
<obspy.core.stream.Stream object at 0x...>
>>> print(st) #doctest: +ELLIPSIS
1 Trace(s) in Stream:
... | 2005-12-19T15:07:54.000000Z - ... | 4000.0 Hz, 8000 samples
"""
# Read file to the internal segy representation.
su_object = readSUFile(filename, endian=byteorder,
unpack_headers=unpack_trace_headers)
# Create the stream object.
stream = Stream()
# Get the endianness from the first trace.
endian = su_object.traces[0].endian
# Loop over all traces.
for tr in su_object.traces:
# Create new Trace object for every segy trace and append to the Stream
# object.
trace = Trace()
stream.append(trace)
# skip data if headonly is set
if headonly:
trace.stats.npts = tr.npts
else:
trace.data = tr.data
trace.stats.su = AttribDict()
# If all values will be unpacked create a normal dictionary.
if unpack_trace_headers:
# Add the trace header as a new attrib dictionary.
header = AttribDict()
for key, value in tr.header.__dict__.items():
setattr(header, key, value)
# Otherwise use the LazyTraceHeaderAttribDict.
else:
# Add the trace header as a new lazy attrib dictionary.
header = LazyTraceHeaderAttribDict(tr.header.unpacked_header,
tr.header.endian)
trace.stats.su.trace_header = header
# Also set the endianness.
trace.stats.su.endian = endian
# The sampling rate should be set for every trace. It is a sample
# interval in microseconds. The only sanity check is that is should be
# larger than 0.
tr_header = trace.stats.su.trace_header
if tr_header.sample_interval_in_ms_for_this_trace > 0:
trace.stats.delta = \
float(tr.header.sample_interval_in_ms_for_this_trace) / \
1E6
# If the year is not zero, calculate the start time. The end time is
# then calculated from the start time and the sampling rate.
# 99 is often used as a placeholder.
if tr_header.year_data_recorded > 0:
year = tr_header.year_data_recorded
# The SEG Y rev 0 standard specifies the year to be a 4 digit
# number. Before that it was unclear if it should be a 2 or 4
# digit number. Old or wrong software might still write 2 digit
# years. Every number <30 will be mapped to 2000-2029 and every
# number between 30 and 99 will be mapped to 1930-1999.
if year < 100:
if year < 30:
year += 2000
else:
year += 1900
julday = tr_header.day_of_year
julday = tr_header.day_of_year
hour = tr_header.hour_of_day
minute = tr_header.minute_of_hour
second = tr_header.second_of_minute
trace.stats.starttime = UTCDateTime(
year=year, julday=julday, hour=hour, minute=minute,
second=second)
return stream
def readSU(filename,
headonly=False,
byteorder=None,
unpack_trace_headers=False,
**kwargs): # @UnusedVariable
"""
Reads a Seismic Unix (SU) file and returns an ObsPy Stream object.
.. warning::
This function should NOT be called directly, it registers via the
ObsPy :func:`~obspy.core.stream.read` function, call this instead.
:type filename: str
:param filename: SU file to be read.
:type headonly: boolean, optional
:param headonly: If set to True, read only the header and omit the waveform
data.
:type byteorder: ``'<'``, ``'>'``, or ``None``
:param byteorder: Determines the endianness of the file. Either ``'>'`` for
big endian or ``'<'`` for little endian. If it is ``None``, it will try
to autodetect the endianness. The endianness is always valid for the
whole file. Defaults to ``None``.
:type unpack_trace_headers: bool, optional
:param unpack_trace_headers: Determines whether or not all trace header
values will be unpacked during reading. If ``False`` it will greatly
enhance performance and especially memory usage with large files. The
header values can still be accessed and will be calculated on the fly
but tab completion will no longer work. Look in the headers.py for a
list of all possible trace header values. Defaults to ``False``.
:returns: A ObsPy :class:`~obspy.core.stream.Stream` object.
.. rubric:: Example
>>> from obspy import read
>>> st = read("/path/to/1.su_first_trace")
>>> st #doctest: +ELLIPSIS
<obspy.core.stream.Stream object at 0x...>
>>> print(st) #doctest: +ELLIPSIS
1 Trace(s) in Stream:
... | 2005-12-19T15:07:54.000000Z - ... | 4000.0 Hz, 8000 samples
"""
# Read file to the internal segy representation.
su_object = readSUFile(filename,
endian=byteorder,
unpack_headers=unpack_trace_headers)
# Create the stream object.
stream = Stream()
# Get the endianness from the first trace.
endian = su_object.traces[0].endian
# Loop over all traces.
for tr in su_object.traces:
# Create new Trace object for every segy trace and append to the Stream
# object.
trace = Trace()
stream.append(trace)
# skip data if headonly is set
if headonly:
trace.stats.npts = tr.npts
else:
trace.data = tr.data
trace.stats.su = AttribDict()
# If all values will be unpacked create a normal dictionary.
if unpack_trace_headers:
# Add the trace header as a new attrib dictionary.
header = AttribDict()
for key, value in tr.header.__dict__.iteritems():
setattr(header, key, value)
# Otherwise use the LazyTraceHeaderAttribDict.
else:
# Add the trace header as a new lazy attrib dictionary.
header = LazyTraceHeaderAttribDict(tr.header.unpacked_header,
tr.header.endian)
trace.stats.su.trace_header = header
# Also set the endianness.
trace.stats.su.endian = endian
# The sampling rate should be set for every trace. It is a sample
# interval in microseconds. The only sanity check is that is should be
# larger than 0.
tr_header = trace.stats.su.trace_header
if tr_header.sample_interval_in_ms_for_this_trace > 0:
trace.stats.delta = \
float(tr.header.sample_interval_in_ms_for_this_trace) / \
1E6
# If the year is not zero, calculate the start time. The end time is
# then calculated from the start time and the sampling rate.
# 99 is often used as a placeholder.
if tr_header.year_data_recorded > 0:
year = tr_header.year_data_recorded
# The SEG Y rev 0 standard specifies the year to be a 4 digit
# number. Before that it was unclear if it should be a 2 or 4
# digit number. Old or wrong software might still write 2 digit
# years. Every number <30 will be mapped to 2000-2029 and every
# number between 30 and 99 will be mapped to 1930-1999.
if year < 100:
if year < 30:
year += 2000
else:
year += 1900
julday = tr_header.day_of_year
julday = tr_header.day_of_year
hour = tr_header.hour_of_day
minute = tr_header.minute_of_hour
second = tr_header.second_of_minute
trace.stats.starttime = UTCDateTime(year=year,
julday=julday,
hour=hour,
minute=minute,
second=second)
return stream