def test_read_truncated_header_raises_eoferror(self, trace_header_written, endian, random):
trace_header_packer = make_header_packer(TraceHeaderRev1, endian)
buffer = trace_header_packer.pack(trace_header_written)
truncate_pos = random.randrange(0, len(buffer) - 1)
truncated_buffer = buffer[:truncate_pos]
with BytesIO(truncated_buffer) as fh:
with raises(EOFError):
toolkit.read_trace_header(fh, trace_header_packer, pos=0)
def test_read_truncated_header_raises_eoferror(self, trace_header_written,
endian, random):
trace_header_packer = make_header_packer(TraceHeaderRev1, endian)
buffer = trace_header_packer.pack(trace_header_written)
truncate_pos = random.randrange(0, len(buffer) - 1)
truncated_buffer = buffer[:truncate_pos]
with BytesIO(truncated_buffer) as fh:
with raises(EOFError):
toolkit.read_trace_header(fh, trace_header_packer, pos=0)
def write_trace_header(self,trace_index,trace_header,force=True):
"""
Write a trace header in place
"""
pos=self.trace_position(trace_index)
try:
read_trace_header(self._fh, self._trace_header_packer, pos=pos)
except Exception as e:
print ("Could not read a trace header from trace_index={}, skipping writting. Pass force=False to force. Exception: {}".format(trace_index),e)
else:
write_trace_header(self._fh,trace_header,self._trace_header_packer,pos)
def write_trace_header(self, trace_index, trace_header, force=True):
"""
Write a trace header in place
"""
pos = self.trace_position(trace_index)
try:
read_trace_header(self._fh, self._trace_header_packer, pos=pos)
except Exception as e:
print(
"Could not read a trace header from trace_index={}, skipping writting. Pass force=False to force. Exception: {}".format(
trace_index
),
e,
)
else:
write_trace_header(self._fh, trace_header, self._trace_header_packer, pos)
def test_read_header_successfully(self, trace_header_written, endian):
trace_header_packer = make_header_packer(TraceHeaderRev1, endian)
buffer = trace_header_packer.pack(trace_header_written)
with BytesIO(buffer) as fh:
trace_header = toolkit.read_trace_header(fh,
trace_header_packer,
pos=0)
assert are_equal(trace_header_written, trace_header)
def trace_header(self, trace_index, header_packer_override=None):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
header_packer_override: Override the default header packer (for example
to more efficiently extract only a few fields)
Returns:
A TraceHeader corresponding to the requested trace_samples.
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index {} out of range".format(trace_index))
header_packer = self._trace_header_packer if header_packer_override is None else header_packer_override
pos = self._trace_offset_catalog[trace_index]
trace_header = read_trace_header(self._fh, header_packer, pos)
return trace_header
def trace_header(self, trace_index, header_packer_override=None):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
header_packer_override: Override the default header packer (for example
to more efficiently extract only a few fields)
Returns:
A TraceHeader corresponding to the requested trace_samples.
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index {} out of range".format(trace_index))
header_packer = self._trace_header_packer if header_packer_override is None else header_packer_override
pos = self._trace_offset_catalog[trace_index]
trace_header = read_trace_header(self._fh, header_packer, pos)
return trace_header
def trace_header(self, trace_index):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
Returns:
A TraceHeader corresponding to the requested trace_samples.
Example:
first_trace_header, first_trace_samples = segy_reader.trace_samples(0)
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index {} out of range".format(trace_index))
pos = self._trace_offset_catalog[trace_index]
trace_header = read_trace_header(self._fh, self._trace_header_format, pos)
return trace_header
def trace_header(self, trace_index):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
Returns:
A TraceHeader corresponding to the requested trace_samples.
Example:
first_trace_header, first_trace_samples = segy_reader.trace_samples(0)
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index {} out of range".format(trace_index))
pos = self._trace_offset_catalog[trace_index]
trace_header = read_trace_header(self._fh, self._trace_header_packer,
pos)
return trace_header
def test_read_header_successfully(self, trace_header_written, endian):
trace_header_packer = make_header_packer(TraceHeaderRev1, endian)
buffer = trace_header_packer.pack(trace_header_written)
with BytesIO(buffer) as fh:
trace_header = toolkit.read_trace_header(fh, trace_header_packer, pos=0)
assert are_equal(trace_header_written, trace_header)
