def __init__(self, arg, x=None, y=None, tracenumbers=None, copyFrom=None):
"""
Input:
filename: The name of the 2D data file
"""
if isinstance(arg, basestring):
filename = arg
infile = BinaryFile(filename, 'rb')
self._read_header(infile)
self._read_traces(infile)
infile.close()
else:
if x is None or y is None:
raise ValueError('When creating a new data2d object, '\
'x and y must both be specified.')
self._new_file(arg, x, y, tracenumbers, copyFrom)
def __init__(self, arg, x=None, y=None, tracenumbers=None, copyFrom=None):
"""
Input:
filename: The name of the 2D data file
"""
if isinstance(arg, basestring):
filename = arg
infile = BinaryFile(filename, 'rb')
self._read_header(infile)
self._read_traces(infile)
infile.close()
else:
if x is None or y is None:
raise ValueError('When creating a new data2d object, '\
'x and y must both be specified.')
self._new_file(arg, x, y, tracenumbers, copyFrom)
class GeoprobeVolumeFileV2(object):
"""Low-level operations for reading and writing to Geoprobe Volume format
version 2.0 seismic data files."""
def __init__(self, filename, mode):
self.filename = filename
self.mode = mode
self._file = BinaryFile(self.filename, self.mode)
def is_valid(self):
"""Returns a boolean indicating whether this is a valid file."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
volSize = os.stat(self.filename).st_size
predSize = nx*ny*nz + _headerLength
if (header['magicNum'] != 43970) or (volSize != predSize):
return False
else:
return True
def read_header(self):
"""Reads and returns the header of a geoprobe volume."""
header = dict()
for varname, info in _headerDef.iteritems():
self._file.seek(info['offset'])
value = self._file.readBinary(info['type'])
header[varname] = value
return header
def read_data(self):
"""Reads an entire Geoprobe volume into memory and returns
a numpy array contining the volume."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
dat = np.fromfile(self.filename, dtype=np.uint8)
dat = dat[_headerLength:]
dat = dat.reshape((nz, ny, nx)).T
return dat
def memmap_data(self):
"""Return an object similar to a memory-mapped numpy array."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
dat = np.memmap(filename=self.filename, mode='r',
offset=_headerLength, order='F',
shape=(nx, ny, nz)
)
return dat
def write_header(self, header):
"""Write the values in the dict "header" to the file."""
for varname, info in _headerDef.iteritems():
value = header.get(varname, info['default'])
self._file.seek(info['offset'])
self._file.writeBinary(info['type'], value)
def write_data(self, data):
"""Writes a geoprobe volume to disk."""
self._file.seek(_headerLength)
# Write to file in Fortran order...
# Not using data.ravel('F'), as it appears to make a copy if the
# array is C-ordered (doubling memory usage). Instead, we just
# write the transpose with the tofile method. (tofile writes in
# C-order regardless of the order of the input array, thus
# requring the transpose for both F and C ordered arrays)
data.T.tofile(self._file)
def close(self):
return self._file.close()
def write(self, outfile):
if isinstance(outfile , basestring):
outfile = BinaryFile(outfile, 'wb')
self._write_header(outfile)
self._write_traces(outfile)
outfile.close()
def write(self, outfile):
if isinstance(outfile, basestring):
outfile = BinaryFile(outfile, 'wb')
self._write_header(outfile)
self._write_traces(outfile)
outfile.close()
class GeoprobeVolumeFileV2(object):
"""Low-level operations for reading and writing to Geoprobe Volume format
version 2.0 seismic data files."""
_magic_number = 43970
def __init__(self, filename, mode):
self.filename = filename
self.mode = mode
self._file = BinaryFile(self.filename, self.mode)
def is_valid(self):
"""Returns a boolean indicating whether this is a valid file."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
volSize = os.stat(self.filename).st_size
predSize = nx*ny*nz + _headerLength
if (header['magicNum'] != self._magic_number) or (volSize != predSize):
return False
else:
return True
def read_header(self):
"""Reads and returns the header of a geoprobe volume."""
header = dict()
for varname, info in _headerDef.iteritems():
self._file.seek(info['offset'])
value = self._file.readBinary(info['type'])
header[varname] = value
return header
def read_data(self):
"""Reads an entire Geoprobe volume into memory and returns
a numpy array contining the volume."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
dat = np.fromfile(self.filename, dtype=np.uint8)
dat = dat[_headerLength:]
dat = dat.reshape((nz, ny, nx)).T
return dat
def memmap_data(self):
"""Return an object similar to a memory-mapped numpy array."""
header = self.read_header()
nx, ny, nz = [header[item] for item in ('_nx', '_ny', '_nz')]
dat = np.memmap(filename=self.filename, mode='r',
offset=_headerLength, order='F',
shape=(nx, ny, nz)
)
return dat
def write_header(self, header):
"""Write the values in the dict "header" to the file."""
for varname, info in _headerDef.iteritems():
value = header.get(varname, info['default'])
self._file.seek(info['offset'])
self._file.writeBinary(info['type'], value)
def write_data(self, data):
"""Writes a geoprobe volume to disk."""
self._file.seek(_headerLength)
# Write to file in Fortran order...
# Not using data.ravel('F'), as it appears to make a copy if the
# array is C-ordered (doubling memory usage). Instead, we just
# write the transpose with the tofile method. (tofile writes in
# C-order regardless of the order of the input array, thus
# requring the transpose for both F and C ordered arrays)
data.T.tofile(self._file)
def close(self):
return self._file.close()
