def test_truncated_read_binary_values_raises_eof_error(self, seg_y_type, num_items, endian, data):
assume(seg_y_type != SegYType.IBM)
ctype = SEG_Y_TYPE_TO_CTYPE[seg_y_type]
c_format = ''.join(map(str, (endian, num_items, ctype)))
py_type = PY_TYPES[seg_y_type]
min_value, max_value = LIMITS[seg_y_type]
items_written = data.draw(st.lists(
elements=NUMBER_STRATEGY[py_type](min_value=min_value, max_value=max_value),
min_size=num_items, max_size=num_items))
buffer = struct.pack(c_format, *items_written)
truncate_pos = data.draw(st.integers(min_value=0, max_value=max(0, len(buffer) - 1)))
truncated_buffer = buffer[:truncate_pos]
with BytesIO(truncated_buffer) as fh:
with raises(EOFError):
toolkit.read_binary_values(fh, 0, seg_y_type, num_items, endian)
def test_read_binary_values_successfully(self, seg_y_type, num_items, endian, data):
assume(seg_y_type != SegYType.IBM)
ctype = SEG_Y_TYPE_TO_CTYPE[seg_y_type]
c_format = ''.join(map(str, (endian, num_items, ctype)))
py_type = PY_TYPES[seg_y_type]
min_value, max_value = LIMITS[seg_y_type]
items_written = data.draw(st.lists(
elements=NUMBER_STRATEGY[py_type](min_value=min_value, max_value=max_value),
min_size=num_items, max_size=num_items))
buffer = struct.pack(c_format, *items_written)
with BytesIO(buffer) as fh:
items_read = toolkit.read_binary_values(fh, 0, seg_y_type, num_items, endian)
assert all(a == b for a, b in zip_longest(items_read, items_read))
def trace_samples(self, trace_index, start=None, stop=None):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
start: Optional zero-based start sample index. The default
is to read from the first (i.e. zeroth) sample.
stop: Optional zero-based stop sample index. Following Python
slice convention this is one beyond the end.
Returns:
A sequence of numeric trace_samples samples.
Example:
first_trace_samples = segy_reader.trace_samples(0)
part_of_second_trace_samples = segy_reader.trace_samples(1, 1000, 2000)
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index out of range.")
num_samples_in_trace = self.num_trace_samples(trace_index)
start_sample = start if start is not None else 0
stop_sample = stop if stop is not None else num_samples_in_trace
if not (0 <= stop_sample <= num_samples_in_trace):
raise ValueError(
"trace_samples(): stop value {} out of range 0 to {}".format(
stop, num_samples_in_trace))
if not (0 <= start_sample <= stop_sample):
raise ValueError(
"trace_samples(): start value {} out of range 0 to {}".format(
start, stop_sample))
dsf = self._binary_reel_header.data_sample_format
seg_y_type = DATA_SAMPLE_FORMAT_TO_SEG_Y_TYPE[dsf]
start_pos = (
self._trace_offset_catalog[trace_index] + TRACE_HEADER_NUM_BYTES +
start_sample * size_in_bytes(SEG_Y_TYPE_TO_CTYPE[seg_y_type]))
num_samples_to_read = stop_sample - start_sample
trace_values = read_binary_values(self._fh, start_pos, seg_y_type,
num_samples_to_read, self._endian)
return trace_values
def trace_samples(self, trace_index, start=None, stop=None):
"""Read a specific trace_samples.
Args:
trace_index: An integer in the range zero to num_traces() - 1
start: Optional zero-based start sample index. The default
is to read from the first (i.e. zeroth) sample.
stop: Optional zero-based stop sample index. Following Python
slice convention this is one beyond the end.
Returns:
A sequence of numeric trace_samples samples.
Example:
first_trace_samples = segy_reader.trace_samples(0)
part_of_second_trace_samples = segy_reader.trace_samples(1, 1000, 2000)
"""
if not (0 <= trace_index < self.num_traces()):
raise ValueError("Trace index out of range.")
num_samples_in_trace = self.num_trace_samples(trace_index)
start_sample = start if start is not None else 0
stop_sample = stop if stop is not None else num_samples_in_trace
if not (0 <= stop_sample <= num_samples_in_trace):
raise ValueError("trace_samples(): stop value {} out of range 0 to {}"
.format(stop, num_samples_in_trace))
if not (0 <= start_sample <= stop_sample):
raise ValueError("trace_samples(): start value {} out of range 0 to {}"
.format(start, stop_sample))
dsf = self._binary_reel_header.data_sample_format
seg_y_type = DATA_SAMPLE_FORMAT_TO_SEG_Y_TYPE[dsf]
start_pos = (self._trace_offset_catalog[trace_index]
+ TRACE_HEADER_NUM_BYTES
+ start_sample * size_in_bytes(SEG_Y_TYPE_TO_CTYPE[seg_y_type]))
num_samples_to_read = stop_sample - start_sample
trace_values = read_binary_values(
self._fh, start_pos, seg_y_type, num_samples_to_read, self._endian)
return trace_values
def test_read_binary_values_successfully(self, seg_y_type, num_items,
endian, data):
assume(seg_y_type != SegYType.IBM)
ctype = SEG_Y_TYPE_TO_CTYPE[seg_y_type]
c_format = ''.join(map(str, (endian, num_items, ctype)))
py_type = PY_TYPES[seg_y_type]
min_value, max_value = LIMITS[seg_y_type]
items_written = data.draw(
st.lists(elements=NUMBER_STRATEGY[py_type](min_value=min_value,
max_value=max_value),
min_size=num_items,
max_size=num_items))
buffer = struct.pack(c_format, *items_written)
with BytesIO(buffer) as fh:
items_read = toolkit.read_binary_values(fh, 0, seg_y_type,
num_items, endian)
assert all(a == b for a, b in zip_longest(items_read, items_read))