def test_large_sample_rate_interval_raises(self):
"""
SEG Y supports a sample interval from 1 to 65535 microseconds in steps
of 1 microsecond. Larger intervals cannot be supported due to the
definition of the SEG Y format. Therefore the smallest possible
sampling rate is ~ 15.26 Hz.
"""
with NamedTemporaryFile() as tf:
outfile = tf.name
# Test for SEG Y.
file = os.path.join(self.path, '1.sgy_first_trace')
segy = _read_segy(file)
segy.stats.textual_file_header = \
_patch_header(segy.stats.textual_file_header)
# Set the largest possible delta value which should just work.
segy[0].stats.delta = 0.065535
_write_segy(segy, outfile)
# Slightly larger should raise.
segy[0].stats.delta = 0.065536
self.assertRaises(SEGYSampleIntervalError, _write_segy, segy,
outfile)
# Same for SU.
file = os.path.join(self.path, '1.su_first_trace')
su = _read_su(file)
# Set the largest possible delta value which should just work.
su[0].stats.delta = 0.065535
_write_su(su, outfile)
# Slightly larger should raise.
su[0].stats.delta = 0.065536
self.assertRaises(SEGYSampleIntervalError, _write_su, su, outfile)
def test_largeSampleRateIntervalRaises(self):
"""
SEG Y supports a sample interval from 1 to 65535 microseconds in steps
of 1 microsecond. Larger intervals cannot be supported due to the
definition of the SEG Y format. Therefore the smallest possible
sampling rate is ~ 15.26 Hz.
"""
with NamedTemporaryFile() as tf:
outfile = tf.name
# Test for SEG Y.
file = os.path.join(self.path, '1.sgy_first_trace')
segy = _read_segy(file)
# Set the largest possible delta value which should just work.
segy[0].stats.delta = 0.065535
_write_segy(segy, outfile)
# Slightly larger should raise.
segy[0].stats.delta = 0.065536
self.assertRaises(SEGYSampleIntervalError, _write_segy, segy,
outfile)
# Same for SU.
file = os.path.join(self.path, '1.su_first_trace')
su = _read_su(file)
# Set the largest possible delta value which should just work.
su[0].stats.delta = 0.065535
_write_su(su, outfile)
# Slightly larger should raise.
su[0].stats.delta = 0.065536
self.assertRaises(SEGYSampleIntervalError, _write_su, su, outfile)
def test_writing_starttime_timestamp_0(self):
"""
If the starttime of the Trace is UTCDateTime(0) it will be interpreted
as a missing starttime is not written. Test if this holds True.
"""
file = os.path.join(self.path, '1.sgy_first_trace')
# This file has a set date!
with open(file, 'rb') as f:
f.seek(3600 + 156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'>5h', date_time)
self.assertEqual([
year == 2005, julday == 353, hour == 15, minute == 7, second == 54
], 5 * [True])
# Read and set zero time.
segy = _read_segy(file)
segy.stats.textual_file_header = \
_patch_header(segy.stats.textual_file_header)
segy[0].stats.starttime = UTCDateTime(0)
with NamedTemporaryFile() as tf:
outfile = tf.name
_write_segy(segy, outfile)
# Check the new date.
with open(outfile, 'rb') as f:
f.seek(3600 + 156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'>5h', date_time)
self.assertEqual(
[year == 0, julday == 0, hour == 0, minute == 0, second == 0],
5 * [True])
# The same for SU.
file = os.path.join(self.path, '1.su_first_trace')
# This file has a set date!
with open(file, 'rb') as f:
f.seek(156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'<5h', date_time)
self.assertEqual([
year == 2005, julday == 353, hour == 15, minute == 7, second == 54
], 5 * [True])
# Read and set zero time.
su = _read_su(file)
su[0].stats.starttime = UTCDateTime(0)
with NamedTemporaryFile() as tf:
outfile = tf.name
_write_su(su, outfile)
# Check the new date.
with open(outfile, 'rb') as f:
f.seek(156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'<5h', date_time)
self.assertEqual(
[year == 0, julday == 0, hour == 0, minute == 0, second == 0],
5 * [True])
def test_writing_starttime_timestamp_0(self):
"""
If the starttime of the Trace is UTCDateTime(0) it will be interpreted
as a missing starttime is not written. Test if this holds True.
"""
file = os.path.join(self.path, '1.sgy_first_trace')
# This file has a set date!
with open(file, 'rb') as f:
f.seek(3600 + 156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'>5h', date_time)
self.assertEqual([year == 2005, julday == 353, hour == 15, minute == 7,
second == 54], 5 * [True])
# Read and set zero time.
segy = _read_segy(file)
segy.stats.textual_file_header = \
_patch_header(segy.stats.textual_file_header)
segy[0].stats.starttime = UTCDateTime(0)
with NamedTemporaryFile() as tf:
outfile = tf.name
_write_segy(segy, outfile)
# Check the new date.
with open(outfile, 'rb') as f:
f.seek(3600 + 156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'>5h', date_time)
self.assertEqual([year == 0, julday == 0, hour == 0, minute == 0,
second == 0], 5 * [True])
# The same for SU.
file = os.path.join(self.path, '1.su_first_trace')
# This file has a set date!
with open(file, 'rb') as f:
f.seek(156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'<5h', date_time)
self.assertEqual([year == 2005, julday == 353, hour == 15, minute == 7,
second == 54], 5 * [True])
# Read and set zero time.
su = _read_su(file)
su[0].stats.starttime = UTCDateTime(0)
with NamedTemporaryFile() as tf:
outfile = tf.name
_write_su(su, outfile)
# Check the new date.
with open(outfile, 'rb') as f:
f.seek(156, 0)
date_time = f.read(10)
year, julday, hour, minute, second = unpack(b'<5h', date_time)
self.assertEqual([year == 0, julday == 0, hour == 0, minute == 0,
second == 0], 5 * [True])
def test_writing_modified_date(self):
"""
Tests if the date in Trace.stats.starttime is correctly written in SU
and SEGY files.
"""
# Define new date!
new_date = UTCDateTime(2010, 7, 7, 2, 2, 2)
with NamedTemporaryFile() as tf:
outfile = tf.name
# Test for SEGY.
file = os.path.join(self.path, 'example.y_first_trace')
segy = _read_segy(file)
segy[0].stats.starttime = new_date
_write_segy(segy, outfile)
segy_new = _read_segy(outfile)
self.assertEqual(new_date, segy_new[0].stats.starttime)
# Test for SU.
file = os.path.join(self.path, '1.su_first_trace')
su = _read_su(file)
su[0].stats.starttime = new_date
_write_su(su, outfile)
su_new = _read_su(outfile)
self.assertEqual(new_date, su_new[0].stats.starttime)
def test_writingModifiedDate(self):
"""
Tests if the date in Trace.stats.starttime is correctly written in SU
and SEGY files.
"""
# Define new date!
new_date = UTCDateTime(2010, 7, 7, 2, 2, 2)
with NamedTemporaryFile() as tf:
outfile = tf.name
# Test for SEGY.
file = os.path.join(self.path, 'example.y_first_trace')
segy = _read_segy(file)
segy[0].stats.starttime = new_date
_write_segy(segy, outfile)
segy_new = _read_segy(outfile)
self.assertEqual(new_date, segy_new[0].stats.starttime)
# Test for SU.
file = os.path.join(self.path, '1.su_first_trace')
su = _read_su(file)
su[0].stats.starttime = new_date
_write_su(su, outfile)
su_new = _read_su(outfile)
self.assertEqual(new_date, su_new[0].stats.starttime)
