915 lines
26 KiB
Python
915 lines
26 KiB
Python
# IDLSave - a python module to read IDL 'save' files
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# Copyright (c) 2010 Thomas P. Robitaille
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# Many thanks to Craig Markwardt for publishing the Unofficial Format
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# Specification for IDL .sav files, without which this Python module would not
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# exist (http://cow.physics.wisc.edu/~craigm/idl/savefmt).
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# This code was developed by with permission from ITT Visual Information
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# Systems. IDL(r) is a registered trademark of ITT Visual Information Systems,
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# Inc. for their Interactive Data Language software.
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# Permission is hereby granted, free of charge, to any person obtaining a
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# copy of this software and associated documentation files (the "Software"),
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# to deal in the Software without restriction, including without limitation
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# the rights to use, copy, modify, merge, publish, distribute, sublicense,
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# and/or sell copies of the Software, and to permit persons to whom the
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# Software is furnished to do so, subject to the following conditions:
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# The above copyright notice and this permission notice shall be included in
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# all copies or substantial portions of the Software.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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# DEALINGS IN THE SOFTWARE.
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__all__ = ['readsav']
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import struct
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import numpy as np
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import tempfile
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import zlib
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import warnings
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# Define the different data types that can be found in an IDL save file
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DTYPE_DICT = {1: '>u1',
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2: '>i2',
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3: '>i4',
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4: '>f4',
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5: '>f8',
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6: '>c8',
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7: '|O',
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8: '|O',
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9: '>c16',
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10: '|O',
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11: '|O',
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12: '>u2',
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13: '>u4',
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14: '>i8',
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15: '>u8'}
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# Define the different record types that can be found in an IDL save file
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RECTYPE_DICT = {0: "START_MARKER",
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1: "COMMON_VARIABLE",
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2: "VARIABLE",
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3: "SYSTEM_VARIABLE",
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6: "END_MARKER",
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10: "TIMESTAMP",
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12: "COMPILED",
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13: "IDENTIFICATION",
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14: "VERSION",
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15: "HEAP_HEADER",
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16: "HEAP_DATA",
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17: "PROMOTE64",
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19: "NOTICE",
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20: "DESCRIPTION"}
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# Define a dictionary to contain structure definitions
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STRUCT_DICT = {}
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def _align_32(f):
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'''Align to the next 32-bit position in a file'''
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pos = f.tell()
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if pos % 4 != 0:
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f.seek(pos + 4 - pos % 4)
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return
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def _skip_bytes(f, n):
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'''Skip `n` bytes'''
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f.read(n)
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return
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def _read_bytes(f, n):
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'''Read the next `n` bytes'''
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return f.read(n)
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def _read_byte(f):
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'''Read a single byte'''
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return np.uint8(struct.unpack('>B', f.read(4)[:1])[0])
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def _read_long(f):
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'''Read a signed 32-bit integer'''
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return np.int32(struct.unpack('>l', f.read(4))[0])
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def _read_int16(f):
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'''Read a signed 16-bit integer'''
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return np.int16(struct.unpack('>h', f.read(4)[2:4])[0])
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def _read_int32(f):
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'''Read a signed 32-bit integer'''
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return np.int32(struct.unpack('>i', f.read(4))[0])
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def _read_int64(f):
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'''Read a signed 64-bit integer'''
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return np.int64(struct.unpack('>q', f.read(8))[0])
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def _read_uint16(f):
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'''Read an unsigned 16-bit integer'''
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return np.uint16(struct.unpack('>H', f.read(4)[2:4])[0])
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def _read_uint32(f):
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'''Read an unsigned 32-bit integer'''
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return np.uint32(struct.unpack('>I', f.read(4))[0])
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def _read_uint64(f):
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'''Read an unsigned 64-bit integer'''
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return np.uint64(struct.unpack('>Q', f.read(8))[0])
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def _read_float32(f):
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'''Read a 32-bit float'''
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return np.float32(struct.unpack('>f', f.read(4))[0])
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def _read_float64(f):
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'''Read a 64-bit float'''
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return np.float64(struct.unpack('>d', f.read(8))[0])
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class Pointer:
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'''Class used to define pointers'''
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def __init__(self, index):
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self.index = index
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return
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class ObjectPointer(Pointer):
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'''Class used to define object pointers'''
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pass
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def _read_string(f):
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'''Read a string'''
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length = _read_long(f)
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if length > 0:
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chars = _read_bytes(f, length).decode('latin1')
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_align_32(f)
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else:
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chars = ''
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return chars
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def _read_string_data(f):
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'''Read a data string (length is specified twice)'''
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length = _read_long(f)
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if length > 0:
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length = _read_long(f)
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string_data = _read_bytes(f, length)
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_align_32(f)
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else:
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string_data = ''
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return string_data
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def _read_data(f, dtype):
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'''Read a variable with a specified data type'''
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if dtype == 1:
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if _read_int32(f) != 1:
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raise Exception("Error occurred while reading byte variable")
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return _read_byte(f)
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elif dtype == 2:
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return _read_int16(f)
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elif dtype == 3:
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return _read_int32(f)
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elif dtype == 4:
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return _read_float32(f)
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elif dtype == 5:
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return _read_float64(f)
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elif dtype == 6:
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real = _read_float32(f)
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imag = _read_float32(f)
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return np.complex64(real + imag * 1j)
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elif dtype == 7:
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return _read_string_data(f)
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elif dtype == 8:
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raise Exception("Should not be here - please report this")
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elif dtype == 9:
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real = _read_float64(f)
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imag = _read_float64(f)
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return np.complex128(real + imag * 1j)
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elif dtype == 10:
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return Pointer(_read_int32(f))
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elif dtype == 11:
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return ObjectPointer(_read_int32(f))
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elif dtype == 12:
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return _read_uint16(f)
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elif dtype == 13:
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return _read_uint32(f)
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elif dtype == 14:
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return _read_int64(f)
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elif dtype == 15:
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return _read_uint64(f)
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else:
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raise Exception("Unknown IDL type: %i - please report this" % dtype)
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def _read_structure(f, array_desc, struct_desc):
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'''
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Read a structure, with the array and structure descriptors given as
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`array_desc` and `structure_desc` respectively.
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'''
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nrows = array_desc['nelements']
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columns = struct_desc['tagtable']
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dtype = []
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for col in columns:
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if col['structure'] or col['array']:
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dtype.append(((col['name'].lower(), col['name']), np.object_))
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else:
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if col['typecode'] in DTYPE_DICT:
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dtype.append(((col['name'].lower(), col['name']),
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DTYPE_DICT[col['typecode']]))
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else:
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raise Exception("Variable type %i not implemented" %
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col['typecode'])
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structure = np.recarray((nrows, ), dtype=dtype)
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for i in range(nrows):
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for col in columns:
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dtype = col['typecode']
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if col['structure']:
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structure[col['name']][i] = _read_structure(f,
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struct_desc['arrtable'][col['name']],
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struct_desc['structtable'][col['name']])
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elif col['array']:
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structure[col['name']][i] = _read_array(f, dtype,
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struct_desc['arrtable'][col['name']])
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else:
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structure[col['name']][i] = _read_data(f, dtype)
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# Reshape structure if needed
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if array_desc['ndims'] > 1:
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dims = array_desc['dims'][:int(array_desc['ndims'])]
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dims.reverse()
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structure = structure.reshape(dims)
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return structure
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def _read_array(f, typecode, array_desc):
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'''
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Read an array of type `typecode`, with the array descriptor given as
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`array_desc`.
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'''
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if typecode in [1, 3, 4, 5, 6, 9, 13, 14, 15]:
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if typecode == 1:
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nbytes = _read_int32(f)
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if nbytes != array_desc['nbytes']:
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warnings.warn("Not able to verify number of bytes from header")
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# Read bytes as numpy array
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array = np.frombuffer(f.read(array_desc['nbytes']),
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dtype=DTYPE_DICT[typecode])
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elif typecode in [2, 12]:
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# These are 2 byte types, need to skip every two as they are not packed
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array = np.frombuffer(f.read(array_desc['nbytes']*2),
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dtype=DTYPE_DICT[typecode])[1::2]
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else:
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# Read bytes into list
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array = []
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for i in range(array_desc['nelements']):
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dtype = typecode
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data = _read_data(f, dtype)
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array.append(data)
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array = np.array(array, dtype=np.object_)
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# Reshape array if needed
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if array_desc['ndims'] > 1:
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dims = array_desc['dims'][:int(array_desc['ndims'])]
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dims.reverse()
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array = array.reshape(dims)
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# Go to next alignment position
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_align_32(f)
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return array
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def _read_record(f):
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'''Function to read in a full record'''
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record = {'rectype': _read_long(f)}
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nextrec = _read_uint32(f)
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nextrec += _read_uint32(f) * 2**32
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_skip_bytes(f, 4)
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if not record['rectype'] in RECTYPE_DICT:
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raise Exception("Unknown RECTYPE: %i" % record['rectype'])
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record['rectype'] = RECTYPE_DICT[record['rectype']]
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if record['rectype'] in ["VARIABLE", "HEAP_DATA"]:
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if record['rectype'] == "VARIABLE":
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record['varname'] = _read_string(f)
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else:
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record['heap_index'] = _read_long(f)
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_skip_bytes(f, 4)
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rectypedesc = _read_typedesc(f)
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if rectypedesc['typecode'] == 0:
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if nextrec == f.tell():
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record['data'] = None # Indicates NULL value
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else:
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raise ValueError("Unexpected type code: 0")
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else:
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varstart = _read_long(f)
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if varstart != 7:
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raise Exception("VARSTART is not 7")
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if rectypedesc['structure']:
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record['data'] = _read_structure(f, rectypedesc['array_desc'],
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rectypedesc['struct_desc'])
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elif rectypedesc['array']:
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record['data'] = _read_array(f, rectypedesc['typecode'],
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rectypedesc['array_desc'])
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else:
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dtype = rectypedesc['typecode']
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record['data'] = _read_data(f, dtype)
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elif record['rectype'] == "TIMESTAMP":
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_skip_bytes(f, 4*256)
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record['date'] = _read_string(f)
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record['user'] = _read_string(f)
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record['host'] = _read_string(f)
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elif record['rectype'] == "VERSION":
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record['format'] = _read_long(f)
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record['arch'] = _read_string(f)
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record['os'] = _read_string(f)
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record['release'] = _read_string(f)
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elif record['rectype'] == "IDENTIFICATON":
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record['author'] = _read_string(f)
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record['title'] = _read_string(f)
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record['idcode'] = _read_string(f)
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elif record['rectype'] == "NOTICE":
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record['notice'] = _read_string(f)
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elif record['rectype'] == "DESCRIPTION":
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record['description'] = _read_string_data(f)
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elif record['rectype'] == "HEAP_HEADER":
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record['nvalues'] = _read_long(f)
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record['indices'] = [_read_long(f) for _ in range(record['nvalues'])]
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elif record['rectype'] == "COMMONBLOCK":
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record['nvars'] = _read_long(f)
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record['name'] = _read_string(f)
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record['varnames'] = [_read_string(f) for _ in range(record['nvars'])]
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elif record['rectype'] == "END_MARKER":
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record['end'] = True
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elif record['rectype'] == "UNKNOWN":
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warnings.warn("Skipping UNKNOWN record")
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elif record['rectype'] == "SYSTEM_VARIABLE":
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warnings.warn("Skipping SYSTEM_VARIABLE record")
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else:
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raise Exception("record['rectype']=%s not implemented" %
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record['rectype'])
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f.seek(nextrec)
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return record
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def _read_typedesc(f):
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'''Function to read in a type descriptor'''
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typedesc = {'typecode': _read_long(f), 'varflags': _read_long(f)}
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if typedesc['varflags'] & 2 == 2:
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raise Exception("System variables not implemented")
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typedesc['array'] = typedesc['varflags'] & 4 == 4
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typedesc['structure'] = typedesc['varflags'] & 32 == 32
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if typedesc['structure']:
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typedesc['array_desc'] = _read_arraydesc(f)
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typedesc['struct_desc'] = _read_structdesc(f)
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elif typedesc['array']:
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typedesc['array_desc'] = _read_arraydesc(f)
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return typedesc
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def _read_arraydesc(f):
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'''Function to read in an array descriptor'''
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arraydesc = {'arrstart': _read_long(f)}
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if arraydesc['arrstart'] == 8:
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_skip_bytes(f, 4)
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arraydesc['nbytes'] = _read_long(f)
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arraydesc['nelements'] = _read_long(f)
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arraydesc['ndims'] = _read_long(f)
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_skip_bytes(f, 8)
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arraydesc['nmax'] = _read_long(f)
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arraydesc['dims'] = [_read_long(f) for _ in range(arraydesc['nmax'])]
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elif arraydesc['arrstart'] == 18:
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warnings.warn("Using experimental 64-bit array read")
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_skip_bytes(f, 8)
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arraydesc['nbytes'] = _read_uint64(f)
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arraydesc['nelements'] = _read_uint64(f)
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arraydesc['ndims'] = _read_long(f)
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_skip_bytes(f, 8)
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arraydesc['nmax'] = 8
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arraydesc['dims'] = []
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for d in range(arraydesc['nmax']):
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v = _read_long(f)
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if v != 0:
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raise Exception("Expected a zero in ARRAY_DESC")
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arraydesc['dims'].append(_read_long(f))
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else:
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raise Exception("Unknown ARRSTART: %i" % arraydesc['arrstart'])
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return arraydesc
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def _read_structdesc(f):
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'''Function to read in a structure descriptor'''
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structdesc = {}
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structstart = _read_long(f)
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if structstart != 9:
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raise Exception("STRUCTSTART should be 9")
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structdesc['name'] = _read_string(f)
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predef = _read_long(f)
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structdesc['ntags'] = _read_long(f)
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structdesc['nbytes'] = _read_long(f)
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structdesc['predef'] = predef & 1
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structdesc['inherits'] = predef & 2
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structdesc['is_super'] = predef & 4
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if not structdesc['predef']:
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structdesc['tagtable'] = [_read_tagdesc(f)
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for _ in range(structdesc['ntags'])]
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for tag in structdesc['tagtable']:
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tag['name'] = _read_string(f)
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structdesc['arrtable'] = {tag['name']: _read_arraydesc(f)
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for tag in structdesc['tagtable']
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if tag['array']}
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structdesc['structtable'] = {tag['name']: _read_structdesc(f)
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for tag in structdesc['tagtable']
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if tag['structure']}
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if structdesc['inherits'] or structdesc['is_super']:
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structdesc['classname'] = _read_string(f)
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structdesc['nsupclasses'] = _read_long(f)
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structdesc['supclassnames'] = [
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_read_string(f) for _ in range(structdesc['nsupclasses'])]
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structdesc['supclasstable'] = [
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_read_structdesc(f) for _ in range(structdesc['nsupclasses'])]
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STRUCT_DICT[structdesc['name']] = structdesc
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else:
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if not structdesc['name'] in STRUCT_DICT:
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raise Exception("PREDEF=1 but can't find definition")
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structdesc = STRUCT_DICT[structdesc['name']]
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return structdesc
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def _read_tagdesc(f):
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'''Function to read in a tag descriptor'''
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tagdesc = {'offset': _read_long(f)}
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if tagdesc['offset'] == -1:
|
|
tagdesc['offset'] = _read_uint64(f)
|
|
|
|
tagdesc['typecode'] = _read_long(f)
|
|
tagflags = _read_long(f)
|
|
|
|
tagdesc['array'] = tagflags & 4 == 4
|
|
tagdesc['structure'] = tagflags & 32 == 32
|
|
tagdesc['scalar'] = tagdesc['typecode'] in DTYPE_DICT
|
|
# Assume '10'x is scalar
|
|
|
|
return tagdesc
|
|
|
|
|
|
def _replace_heap(variable, heap):
|
|
|
|
if isinstance(variable, Pointer):
|
|
|
|
while isinstance(variable, Pointer):
|
|
|
|
if variable.index == 0:
|
|
variable = None
|
|
else:
|
|
if variable.index in heap:
|
|
variable = heap[variable.index]
|
|
else:
|
|
warnings.warn("Variable referenced by pointer not found "
|
|
"in heap: variable will be set to None")
|
|
variable = None
|
|
|
|
replace, new = _replace_heap(variable, heap)
|
|
|
|
if replace:
|
|
variable = new
|
|
|
|
return True, variable
|
|
|
|
elif isinstance(variable, np.core.records.recarray):
|
|
|
|
# Loop over records
|
|
for ir, record in enumerate(variable):
|
|
|
|
replace, new = _replace_heap(record, heap)
|
|
|
|
if replace:
|
|
variable[ir] = new
|
|
|
|
return False, variable
|
|
|
|
elif isinstance(variable, np.core.records.record):
|
|
|
|
# Loop over values
|
|
for iv, value in enumerate(variable):
|
|
|
|
replace, new = _replace_heap(value, heap)
|
|
|
|
if replace:
|
|
variable[iv] = new
|
|
|
|
return False, variable
|
|
|
|
elif isinstance(variable, np.ndarray):
|
|
|
|
# Loop over values if type is np.object_
|
|
if variable.dtype.type is np.object_:
|
|
|
|
for iv in range(variable.size):
|
|
|
|
replace, new = _replace_heap(variable.item(iv), heap)
|
|
|
|
if replace:
|
|
variable.itemset(iv, new)
|
|
|
|
return False, variable
|
|
|
|
else:
|
|
|
|
return False, variable
|
|
|
|
|
|
class AttrDict(dict):
|
|
'''
|
|
A case-insensitive dictionary with access via item, attribute, and call
|
|
notations:
|
|
|
|
>>> d = AttrDict()
|
|
>>> d['Variable'] = 123
|
|
>>> d['Variable']
|
|
123
|
|
>>> d.Variable
|
|
123
|
|
>>> d.variable
|
|
123
|
|
>>> d('VARIABLE')
|
|
123
|
|
>>> d['missing']
|
|
Traceback (most recent error last):
|
|
...
|
|
KeyError: 'missing'
|
|
>>> d.missing
|
|
Traceback (most recent error last):
|
|
...
|
|
AttributeError: 'AttrDict' object has no attribute 'missing'
|
|
'''
|
|
|
|
def __init__(self, init={}):
|
|
dict.__init__(self, init)
|
|
|
|
def __getitem__(self, name):
|
|
return super().__getitem__(name.lower())
|
|
|
|
def __setitem__(self, key, value):
|
|
return super().__setitem__(key.lower(), value)
|
|
|
|
def __getattr__(self, name):
|
|
try:
|
|
return self.__getitem__(name)
|
|
except KeyError:
|
|
raise AttributeError(
|
|
f"'{type(self)}' object has no attribute '{name}'") from None
|
|
|
|
__setattr__ = __setitem__
|
|
__call__ = __getitem__
|
|
|
|
|
|
def readsav(file_name, idict=None, python_dict=False,
|
|
uncompressed_file_name=None, verbose=False):
|
|
"""
|
|
Read an IDL .sav file.
|
|
|
|
Parameters
|
|
----------
|
|
file_name : str
|
|
Name of the IDL save file.
|
|
idict : dict, optional
|
|
Dictionary in which to insert .sav file variables.
|
|
python_dict : bool, optional
|
|
By default, the object return is not a Python dictionary, but a
|
|
case-insensitive dictionary with item, attribute, and call access
|
|
to variables. To get a standard Python dictionary, set this option
|
|
to True.
|
|
uncompressed_file_name : str, optional
|
|
This option only has an effect for .sav files written with the
|
|
/compress option. If a file name is specified, compressed .sav
|
|
files are uncompressed to this file. Otherwise, readsav will use
|
|
the `tempfile` module to determine a temporary filename
|
|
automatically, and will remove the temporary file upon successfully
|
|
reading it in.
|
|
verbose : bool, optional
|
|
Whether to print out information about the save file, including
|
|
the records read, and available variables.
|
|
|
|
Returns
|
|
-------
|
|
idl_dict : AttrDict or dict
|
|
If `python_dict` is set to False (default), this function returns a
|
|
case-insensitive dictionary with item, attribute, and call access
|
|
to variables. If `python_dict` is set to True, this function
|
|
returns a Python dictionary with all variable names in lowercase.
|
|
If `idict` was specified, then variables are written to the
|
|
dictionary specified, and the updated dictionary is returned.
|
|
|
|
Examples
|
|
--------
|
|
>>> from os.path import dirname, join as pjoin
|
|
>>> import scipy.io as sio
|
|
>>> from scipy.io import readsav
|
|
|
|
Get the filename for an example .sav file from the tests/data directory.
|
|
|
|
>>> data_dir = pjoin(dirname(sio.__file__), 'tests', 'data')
|
|
>>> sav_fname = pjoin(data_dir, 'array_float32_1d.sav')
|
|
|
|
Load the .sav file contents.
|
|
|
|
>>> sav_data = readsav(sav_fname)
|
|
|
|
Get keys of the .sav file contents.
|
|
|
|
>>> print(sav_data.keys())
|
|
dict_keys(['array1d'])
|
|
|
|
Access a content with a key.
|
|
|
|
>>> print(sav_data['array1d'])
|
|
[0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
|
|
0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
|
|
0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
|
|
0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
|
|
0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
|
|
0. 0. 0.]
|
|
|
|
"""
|
|
|
|
# Initialize record and variable holders
|
|
records = []
|
|
if python_dict or idict:
|
|
variables = {}
|
|
else:
|
|
variables = AttrDict()
|
|
|
|
# Open the IDL file
|
|
f = open(file_name, 'rb')
|
|
|
|
# Read the signature, which should be 'SR'
|
|
signature = _read_bytes(f, 2)
|
|
if signature != b'SR':
|
|
raise Exception("Invalid SIGNATURE: %s" % signature)
|
|
|
|
# Next, the record format, which is '\x00\x04' for normal .sav
|
|
# files, and '\x00\x06' for compressed .sav files.
|
|
recfmt = _read_bytes(f, 2)
|
|
|
|
if recfmt == b'\x00\x04':
|
|
pass
|
|
|
|
elif recfmt == b'\x00\x06':
|
|
|
|
if verbose:
|
|
print("IDL Save file is compressed")
|
|
|
|
if uncompressed_file_name:
|
|
fout = open(uncompressed_file_name, 'w+b')
|
|
else:
|
|
fout = tempfile.NamedTemporaryFile(suffix='.sav')
|
|
|
|
if verbose:
|
|
print(" -> expanding to %s" % fout.name)
|
|
|
|
# Write header
|
|
fout.write(b'SR\x00\x04')
|
|
|
|
# Cycle through records
|
|
while True:
|
|
|
|
# Read record type
|
|
rectype = _read_long(f)
|
|
fout.write(struct.pack('>l', int(rectype)))
|
|
|
|
# Read position of next record and return as int
|
|
nextrec = _read_uint32(f)
|
|
nextrec += _read_uint32(f) * 2**32
|
|
|
|
# Read the unknown 4 bytes
|
|
unknown = f.read(4)
|
|
|
|
# Check if the end of the file has been reached
|
|
if RECTYPE_DICT[rectype] == 'END_MARKER':
|
|
modval = np.int64(2**32)
|
|
fout.write(struct.pack('>I', int(nextrec) % modval))
|
|
fout.write(struct.pack('>I', int((nextrec - (nextrec % modval)) / modval)))
|
|
fout.write(unknown)
|
|
break
|
|
|
|
# Find current position
|
|
pos = f.tell()
|
|
|
|
# Decompress record
|
|
rec_string = zlib.decompress(f.read(nextrec-pos))
|
|
|
|
# Find new position of next record
|
|
nextrec = fout.tell() + len(rec_string) + 12
|
|
|
|
# Write out record
|
|
fout.write(struct.pack('>I', int(nextrec % 2**32)))
|
|
fout.write(struct.pack('>I', int((nextrec - (nextrec % 2**32)) / 2**32)))
|
|
fout.write(unknown)
|
|
fout.write(rec_string)
|
|
|
|
# Close the original compressed file
|
|
f.close()
|
|
|
|
# Set f to be the decompressed file, and skip the first four bytes
|
|
f = fout
|
|
f.seek(4)
|
|
|
|
else:
|
|
raise Exception("Invalid RECFMT: %s" % recfmt)
|
|
|
|
# Loop through records, and add them to the list
|
|
while True:
|
|
r = _read_record(f)
|
|
records.append(r)
|
|
if 'end' in r:
|
|
if r['end']:
|
|
break
|
|
|
|
# Close the file
|
|
f.close()
|
|
|
|
# Find heap data variables
|
|
heap = {}
|
|
for r in records:
|
|
if r['rectype'] == "HEAP_DATA":
|
|
heap[r['heap_index']] = r['data']
|
|
|
|
# Find all variables
|
|
for r in records:
|
|
if r['rectype'] == "VARIABLE":
|
|
replace, new = _replace_heap(r['data'], heap)
|
|
if replace:
|
|
r['data'] = new
|
|
variables[r['varname'].lower()] = r['data']
|
|
|
|
if verbose:
|
|
|
|
# Print out timestamp info about the file
|
|
for record in records:
|
|
if record['rectype'] == "TIMESTAMP":
|
|
print("-"*50)
|
|
print("Date: %s" % record['date'])
|
|
print("User: %s" % record['user'])
|
|
print("Host: %s" % record['host'])
|
|
break
|
|
|
|
# Print out version info about the file
|
|
for record in records:
|
|
if record['rectype'] == "VERSION":
|
|
print("-"*50)
|
|
print("Format: %s" % record['format'])
|
|
print("Architecture: %s" % record['arch'])
|
|
print("Operating System: %s" % record['os'])
|
|
print("IDL Version: %s" % record['release'])
|
|
break
|
|
|
|
# Print out identification info about the file
|
|
for record in records:
|
|
if record['rectype'] == "IDENTIFICATON":
|
|
print("-"*50)
|
|
print("Author: %s" % record['author'])
|
|
print("Title: %s" % record['title'])
|
|
print("ID Code: %s" % record['idcode'])
|
|
break
|
|
|
|
# Print out descriptions saved with the file
|
|
for record in records:
|
|
if record['rectype'] == "DESCRIPTION":
|
|
print("-"*50)
|
|
print("Description: %s" % record['description'])
|
|
break
|
|
|
|
print("-"*50)
|
|
print("Successfully read %i records of which:" %
|
|
(len(records)))
|
|
|
|
# Create convenience list of record types
|
|
rectypes = [r['rectype'] for r in records]
|
|
|
|
for rt in set(rectypes):
|
|
if rt != 'END_MARKER':
|
|
print(" - %i are of type %s" % (rectypes.count(rt), rt))
|
|
print("-"*50)
|
|
|
|
if 'VARIABLE' in rectypes:
|
|
print("Available variables:")
|
|
for var in variables:
|
|
print(" - %s [%s]" % (var, type(variables[var])))
|
|
print("-"*50)
|
|
|
|
if idict:
|
|
for var in variables:
|
|
idict[var] = variables[var]
|
|
return idict
|
|
else:
|
|
return variables
|