Updated script that can be controled by Nodejs web app
This commit is contained in:
3
lib/python3.13/site-packages/pandas/io/sas/__init__.py
Normal file
3
lib/python3.13/site-packages/pandas/io/sas/__init__.py
Normal file
@ -0,0 +1,3 @@
|
||||
from pandas.io.sas.sasreader import read_sas
|
||||
|
||||
__all__ = ["read_sas"]
|
Binary file not shown.
Binary file not shown.
756
lib/python3.13/site-packages/pandas/io/sas/sas7bdat.py
Normal file
756
lib/python3.13/site-packages/pandas/io/sas/sas7bdat.py
Normal file
@ -0,0 +1,756 @@
|
||||
"""
|
||||
Read SAS7BDAT files
|
||||
|
||||
Based on code written by Jared Hobbs:
|
||||
https://bitbucket.org/jaredhobbs/sas7bdat
|
||||
|
||||
See also:
|
||||
https://github.com/BioStatMatt/sas7bdat
|
||||
|
||||
Partial documentation of the file format:
|
||||
https://cran.r-project.org/package=sas7bdat/vignettes/sas7bdat.pdf
|
||||
|
||||
Reference for binary data compression:
|
||||
http://collaboration.cmc.ec.gc.ca/science/rpn/biblio/ddj/Website/articles/CUJ/1992/9210/ross/ross.htm
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
from collections import abc
|
||||
from datetime import (
|
||||
datetime,
|
||||
timedelta,
|
||||
)
|
||||
import sys
|
||||
from typing import TYPE_CHECKING
|
||||
|
||||
import numpy as np
|
||||
|
||||
from pandas._libs.byteswap import (
|
||||
read_double_with_byteswap,
|
||||
read_float_with_byteswap,
|
||||
read_uint16_with_byteswap,
|
||||
read_uint32_with_byteswap,
|
||||
read_uint64_with_byteswap,
|
||||
)
|
||||
from pandas._libs.sas import (
|
||||
Parser,
|
||||
get_subheader_index,
|
||||
)
|
||||
from pandas._libs.tslibs.conversion import cast_from_unit_vectorized
|
||||
from pandas.errors import EmptyDataError
|
||||
|
||||
import pandas as pd
|
||||
from pandas import (
|
||||
DataFrame,
|
||||
Timestamp,
|
||||
isna,
|
||||
)
|
||||
|
||||
from pandas.io.common import get_handle
|
||||
import pandas.io.sas.sas_constants as const
|
||||
from pandas.io.sas.sasreader import ReaderBase
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from pandas._typing import (
|
||||
CompressionOptions,
|
||||
FilePath,
|
||||
ReadBuffer,
|
||||
)
|
||||
|
||||
|
||||
_unix_origin = Timestamp("1970-01-01")
|
||||
_sas_origin = Timestamp("1960-01-01")
|
||||
|
||||
|
||||
def _parse_datetime(sas_datetime: float, unit: str):
|
||||
if isna(sas_datetime):
|
||||
return pd.NaT
|
||||
|
||||
if unit == "s":
|
||||
return datetime(1960, 1, 1) + timedelta(seconds=sas_datetime)
|
||||
|
||||
elif unit == "d":
|
||||
return datetime(1960, 1, 1) + timedelta(days=sas_datetime)
|
||||
|
||||
else:
|
||||
raise ValueError("unit must be 'd' or 's'")
|
||||
|
||||
|
||||
def _convert_datetimes(sas_datetimes: pd.Series, unit: str) -> pd.Series:
|
||||
"""
|
||||
Convert to Timestamp if possible, otherwise to datetime.datetime.
|
||||
SAS float64 lacks precision for more than ms resolution so the fit
|
||||
to datetime.datetime is ok.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
sas_datetimes : {Series, Sequence[float]}
|
||||
Dates or datetimes in SAS
|
||||
unit : {'d', 's'}
|
||||
"d" if the floats represent dates, "s" for datetimes
|
||||
|
||||
Returns
|
||||
-------
|
||||
Series
|
||||
Series of datetime64 dtype or datetime.datetime.
|
||||
"""
|
||||
td = (_sas_origin - _unix_origin).as_unit("s")
|
||||
if unit == "s":
|
||||
millis = cast_from_unit_vectorized(
|
||||
sas_datetimes._values, unit="s", out_unit="ms"
|
||||
)
|
||||
dt64ms = millis.view("M8[ms]") + td
|
||||
return pd.Series(dt64ms, index=sas_datetimes.index, copy=False)
|
||||
else:
|
||||
vals = np.array(sas_datetimes, dtype="M8[D]") + td
|
||||
return pd.Series(vals, dtype="M8[s]", index=sas_datetimes.index, copy=False)
|
||||
|
||||
|
||||
class _Column:
|
||||
col_id: int
|
||||
name: str | bytes
|
||||
label: str | bytes
|
||||
format: str | bytes
|
||||
ctype: bytes
|
||||
length: int
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
col_id: int,
|
||||
# These can be bytes when convert_header_text is False
|
||||
name: str | bytes,
|
||||
label: str | bytes,
|
||||
format: str | bytes,
|
||||
ctype: bytes,
|
||||
length: int,
|
||||
) -> None:
|
||||
self.col_id = col_id
|
||||
self.name = name
|
||||
self.label = label
|
||||
self.format = format
|
||||
self.ctype = ctype
|
||||
self.length = length
|
||||
|
||||
|
||||
# SAS7BDAT represents a SAS data file in SAS7BDAT format.
|
||||
class SAS7BDATReader(ReaderBase, abc.Iterator):
|
||||
"""
|
||||
Read SAS files in SAS7BDAT format.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
path_or_buf : path name or buffer
|
||||
Name of SAS file or file-like object pointing to SAS file
|
||||
contents.
|
||||
index : column identifier, defaults to None
|
||||
Column to use as index.
|
||||
convert_dates : bool, defaults to True
|
||||
Attempt to convert dates to Pandas datetime values. Note that
|
||||
some rarely used SAS date formats may be unsupported.
|
||||
blank_missing : bool, defaults to True
|
||||
Convert empty strings to missing values (SAS uses blanks to
|
||||
indicate missing character variables).
|
||||
chunksize : int, defaults to None
|
||||
Return SAS7BDATReader object for iterations, returns chunks
|
||||
with given number of lines.
|
||||
encoding : str, 'infer', defaults to None
|
||||
String encoding acc. to Python standard encodings,
|
||||
encoding='infer' tries to detect the encoding from the file header,
|
||||
encoding=None will leave the data in binary format.
|
||||
convert_text : bool, defaults to True
|
||||
If False, text variables are left as raw bytes.
|
||||
convert_header_text : bool, defaults to True
|
||||
If False, header text, including column names, are left as raw
|
||||
bytes.
|
||||
"""
|
||||
|
||||
_int_length: int
|
||||
_cached_page: bytes | None
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
path_or_buf: FilePath | ReadBuffer[bytes],
|
||||
index=None,
|
||||
convert_dates: bool = True,
|
||||
blank_missing: bool = True,
|
||||
chunksize: int | None = None,
|
||||
encoding: str | None = None,
|
||||
convert_text: bool = True,
|
||||
convert_header_text: bool = True,
|
||||
compression: CompressionOptions = "infer",
|
||||
) -> None:
|
||||
self.index = index
|
||||
self.convert_dates = convert_dates
|
||||
self.blank_missing = blank_missing
|
||||
self.chunksize = chunksize
|
||||
self.encoding = encoding
|
||||
self.convert_text = convert_text
|
||||
self.convert_header_text = convert_header_text
|
||||
|
||||
self.default_encoding = "latin-1"
|
||||
self.compression = b""
|
||||
self.column_names_raw: list[bytes] = []
|
||||
self.column_names: list[str | bytes] = []
|
||||
self.column_formats: list[str | bytes] = []
|
||||
self.columns: list[_Column] = []
|
||||
|
||||
self._current_page_data_subheader_pointers: list[tuple[int, int]] = []
|
||||
self._cached_page = None
|
||||
self._column_data_lengths: list[int] = []
|
||||
self._column_data_offsets: list[int] = []
|
||||
self._column_types: list[bytes] = []
|
||||
|
||||
self._current_row_in_file_index = 0
|
||||
self._current_row_on_page_index = 0
|
||||
self._current_row_in_file_index = 0
|
||||
|
||||
self.handles = get_handle(
|
||||
path_or_buf, "rb", is_text=False, compression=compression
|
||||
)
|
||||
|
||||
self._path_or_buf = self.handles.handle
|
||||
|
||||
# Same order as const.SASIndex
|
||||
self._subheader_processors = [
|
||||
self._process_rowsize_subheader,
|
||||
self._process_columnsize_subheader,
|
||||
self._process_subheader_counts,
|
||||
self._process_columntext_subheader,
|
||||
self._process_columnname_subheader,
|
||||
self._process_columnattributes_subheader,
|
||||
self._process_format_subheader,
|
||||
self._process_columnlist_subheader,
|
||||
None, # Data
|
||||
]
|
||||
|
||||
try:
|
||||
self._get_properties()
|
||||
self._parse_metadata()
|
||||
except Exception:
|
||||
self.close()
|
||||
raise
|
||||
|
||||
def column_data_lengths(self) -> np.ndarray:
|
||||
"""Return a numpy int64 array of the column data lengths"""
|
||||
return np.asarray(self._column_data_lengths, dtype=np.int64)
|
||||
|
||||
def column_data_offsets(self) -> np.ndarray:
|
||||
"""Return a numpy int64 array of the column offsets"""
|
||||
return np.asarray(self._column_data_offsets, dtype=np.int64)
|
||||
|
||||
def column_types(self) -> np.ndarray:
|
||||
"""
|
||||
Returns a numpy character array of the column types:
|
||||
s (string) or d (double)
|
||||
"""
|
||||
return np.asarray(self._column_types, dtype=np.dtype("S1"))
|
||||
|
||||
def close(self) -> None:
|
||||
self.handles.close()
|
||||
|
||||
def _get_properties(self) -> None:
|
||||
# Check magic number
|
||||
self._path_or_buf.seek(0)
|
||||
self._cached_page = self._path_or_buf.read(288)
|
||||
if self._cached_page[0 : len(const.magic)] != const.magic:
|
||||
raise ValueError("magic number mismatch (not a SAS file?)")
|
||||
|
||||
# Get alignment information
|
||||
buf = self._read_bytes(const.align_1_offset, const.align_1_length)
|
||||
if buf == const.u64_byte_checker_value:
|
||||
self.U64 = True
|
||||
self._int_length = 8
|
||||
self._page_bit_offset = const.page_bit_offset_x64
|
||||
self._subheader_pointer_length = const.subheader_pointer_length_x64
|
||||
else:
|
||||
self.U64 = False
|
||||
self._page_bit_offset = const.page_bit_offset_x86
|
||||
self._subheader_pointer_length = const.subheader_pointer_length_x86
|
||||
self._int_length = 4
|
||||
buf = self._read_bytes(const.align_2_offset, const.align_2_length)
|
||||
if buf == const.align_1_checker_value:
|
||||
align1 = const.align_2_value
|
||||
else:
|
||||
align1 = 0
|
||||
|
||||
# Get endianness information
|
||||
buf = self._read_bytes(const.endianness_offset, const.endianness_length)
|
||||
if buf == b"\x01":
|
||||
self.byte_order = "<"
|
||||
self.need_byteswap = sys.byteorder == "big"
|
||||
else:
|
||||
self.byte_order = ">"
|
||||
self.need_byteswap = sys.byteorder == "little"
|
||||
|
||||
# Get encoding information
|
||||
buf = self._read_bytes(const.encoding_offset, const.encoding_length)[0]
|
||||
if buf in const.encoding_names:
|
||||
self.inferred_encoding = const.encoding_names[buf]
|
||||
if self.encoding == "infer":
|
||||
self.encoding = self.inferred_encoding
|
||||
else:
|
||||
self.inferred_encoding = f"unknown (code={buf})"
|
||||
|
||||
# Timestamp is epoch 01/01/1960
|
||||
epoch = datetime(1960, 1, 1)
|
||||
x = self._read_float(
|
||||
const.date_created_offset + align1, const.date_created_length
|
||||
)
|
||||
self.date_created = epoch + pd.to_timedelta(x, unit="s")
|
||||
x = self._read_float(
|
||||
const.date_modified_offset + align1, const.date_modified_length
|
||||
)
|
||||
self.date_modified = epoch + pd.to_timedelta(x, unit="s")
|
||||
|
||||
self.header_length = self._read_uint(
|
||||
const.header_size_offset + align1, const.header_size_length
|
||||
)
|
||||
|
||||
# Read the rest of the header into cached_page.
|
||||
buf = self._path_or_buf.read(self.header_length - 288)
|
||||
self._cached_page += buf
|
||||
# error: Argument 1 to "len" has incompatible type "Optional[bytes]";
|
||||
# expected "Sized"
|
||||
if len(self._cached_page) != self.header_length: # type: ignore[arg-type]
|
||||
raise ValueError("The SAS7BDAT file appears to be truncated.")
|
||||
|
||||
self._page_length = self._read_uint(
|
||||
const.page_size_offset + align1, const.page_size_length
|
||||
)
|
||||
|
||||
def __next__(self) -> DataFrame:
|
||||
da = self.read(nrows=self.chunksize or 1)
|
||||
if da.empty:
|
||||
self.close()
|
||||
raise StopIteration
|
||||
return da
|
||||
|
||||
# Read a single float of the given width (4 or 8).
|
||||
def _read_float(self, offset: int, width: int):
|
||||
assert self._cached_page is not None
|
||||
if width == 4:
|
||||
return read_float_with_byteswap(
|
||||
self._cached_page, offset, self.need_byteswap
|
||||
)
|
||||
elif width == 8:
|
||||
return read_double_with_byteswap(
|
||||
self._cached_page, offset, self.need_byteswap
|
||||
)
|
||||
else:
|
||||
self.close()
|
||||
raise ValueError("invalid float width")
|
||||
|
||||
# Read a single unsigned integer of the given width (1, 2, 4 or 8).
|
||||
def _read_uint(self, offset: int, width: int) -> int:
|
||||
assert self._cached_page is not None
|
||||
if width == 1:
|
||||
return self._read_bytes(offset, 1)[0]
|
||||
elif width == 2:
|
||||
return read_uint16_with_byteswap(
|
||||
self._cached_page, offset, self.need_byteswap
|
||||
)
|
||||
elif width == 4:
|
||||
return read_uint32_with_byteswap(
|
||||
self._cached_page, offset, self.need_byteswap
|
||||
)
|
||||
elif width == 8:
|
||||
return read_uint64_with_byteswap(
|
||||
self._cached_page, offset, self.need_byteswap
|
||||
)
|
||||
else:
|
||||
self.close()
|
||||
raise ValueError("invalid int width")
|
||||
|
||||
def _read_bytes(self, offset: int, length: int):
|
||||
assert self._cached_page is not None
|
||||
if offset + length > len(self._cached_page):
|
||||
self.close()
|
||||
raise ValueError("The cached page is too small.")
|
||||
return self._cached_page[offset : offset + length]
|
||||
|
||||
def _read_and_convert_header_text(self, offset: int, length: int) -> str | bytes:
|
||||
return self._convert_header_text(
|
||||
self._read_bytes(offset, length).rstrip(b"\x00 ")
|
||||
)
|
||||
|
||||
def _parse_metadata(self) -> None:
|
||||
done = False
|
||||
while not done:
|
||||
self._cached_page = self._path_or_buf.read(self._page_length)
|
||||
if len(self._cached_page) <= 0:
|
||||
break
|
||||
if len(self._cached_page) != self._page_length:
|
||||
raise ValueError("Failed to read a meta data page from the SAS file.")
|
||||
done = self._process_page_meta()
|
||||
|
||||
def _process_page_meta(self) -> bool:
|
||||
self._read_page_header()
|
||||
pt = const.page_meta_types + [const.page_amd_type, const.page_mix_type]
|
||||
if self._current_page_type in pt:
|
||||
self._process_page_metadata()
|
||||
is_data_page = self._current_page_type == const.page_data_type
|
||||
is_mix_page = self._current_page_type == const.page_mix_type
|
||||
return bool(
|
||||
is_data_page
|
||||
or is_mix_page
|
||||
or self._current_page_data_subheader_pointers != []
|
||||
)
|
||||
|
||||
def _read_page_header(self) -> None:
|
||||
bit_offset = self._page_bit_offset
|
||||
tx = const.page_type_offset + bit_offset
|
||||
self._current_page_type = (
|
||||
self._read_uint(tx, const.page_type_length) & const.page_type_mask2
|
||||
)
|
||||
tx = const.block_count_offset + bit_offset
|
||||
self._current_page_block_count = self._read_uint(tx, const.block_count_length)
|
||||
tx = const.subheader_count_offset + bit_offset
|
||||
self._current_page_subheaders_count = self._read_uint(
|
||||
tx, const.subheader_count_length
|
||||
)
|
||||
|
||||
def _process_page_metadata(self) -> None:
|
||||
bit_offset = self._page_bit_offset
|
||||
|
||||
for i in range(self._current_page_subheaders_count):
|
||||
offset = const.subheader_pointers_offset + bit_offset
|
||||
total_offset = offset + self._subheader_pointer_length * i
|
||||
|
||||
subheader_offset = self._read_uint(total_offset, self._int_length)
|
||||
total_offset += self._int_length
|
||||
|
||||
subheader_length = self._read_uint(total_offset, self._int_length)
|
||||
total_offset += self._int_length
|
||||
|
||||
subheader_compression = self._read_uint(total_offset, 1)
|
||||
total_offset += 1
|
||||
|
||||
subheader_type = self._read_uint(total_offset, 1)
|
||||
|
||||
if (
|
||||
subheader_length == 0
|
||||
or subheader_compression == const.truncated_subheader_id
|
||||
):
|
||||
continue
|
||||
|
||||
subheader_signature = self._read_bytes(subheader_offset, self._int_length)
|
||||
subheader_index = get_subheader_index(subheader_signature)
|
||||
subheader_processor = self._subheader_processors[subheader_index]
|
||||
|
||||
if subheader_processor is None:
|
||||
f1 = subheader_compression in (const.compressed_subheader_id, 0)
|
||||
f2 = subheader_type == const.compressed_subheader_type
|
||||
if self.compression and f1 and f2:
|
||||
self._current_page_data_subheader_pointers.append(
|
||||
(subheader_offset, subheader_length)
|
||||
)
|
||||
else:
|
||||
self.close()
|
||||
raise ValueError(
|
||||
f"Unknown subheader signature {subheader_signature}"
|
||||
)
|
||||
else:
|
||||
subheader_processor(subheader_offset, subheader_length)
|
||||
|
||||
def _process_rowsize_subheader(self, offset: int, length: int) -> None:
|
||||
int_len = self._int_length
|
||||
lcs_offset = offset
|
||||
lcp_offset = offset
|
||||
if self.U64:
|
||||
lcs_offset += 682
|
||||
lcp_offset += 706
|
||||
else:
|
||||
lcs_offset += 354
|
||||
lcp_offset += 378
|
||||
|
||||
self.row_length = self._read_uint(
|
||||
offset + const.row_length_offset_multiplier * int_len,
|
||||
int_len,
|
||||
)
|
||||
self.row_count = self._read_uint(
|
||||
offset + const.row_count_offset_multiplier * int_len,
|
||||
int_len,
|
||||
)
|
||||
self.col_count_p1 = self._read_uint(
|
||||
offset + const.col_count_p1_multiplier * int_len, int_len
|
||||
)
|
||||
self.col_count_p2 = self._read_uint(
|
||||
offset + const.col_count_p2_multiplier * int_len, int_len
|
||||
)
|
||||
mx = const.row_count_on_mix_page_offset_multiplier * int_len
|
||||
self._mix_page_row_count = self._read_uint(offset + mx, int_len)
|
||||
self._lcs = self._read_uint(lcs_offset, 2)
|
||||
self._lcp = self._read_uint(lcp_offset, 2)
|
||||
|
||||
def _process_columnsize_subheader(self, offset: int, length: int) -> None:
|
||||
int_len = self._int_length
|
||||
offset += int_len
|
||||
self.column_count = self._read_uint(offset, int_len)
|
||||
if self.col_count_p1 + self.col_count_p2 != self.column_count:
|
||||
print(
|
||||
f"Warning: column count mismatch ({self.col_count_p1} + "
|
||||
f"{self.col_count_p2} != {self.column_count})\n"
|
||||
)
|
||||
|
||||
# Unknown purpose
|
||||
def _process_subheader_counts(self, offset: int, length: int) -> None:
|
||||
pass
|
||||
|
||||
def _process_columntext_subheader(self, offset: int, length: int) -> None:
|
||||
offset += self._int_length
|
||||
text_block_size = self._read_uint(offset, const.text_block_size_length)
|
||||
|
||||
buf = self._read_bytes(offset, text_block_size)
|
||||
cname_raw = buf[0:text_block_size].rstrip(b"\x00 ")
|
||||
self.column_names_raw.append(cname_raw)
|
||||
|
||||
if len(self.column_names_raw) == 1:
|
||||
compression_literal = b""
|
||||
for cl in const.compression_literals:
|
||||
if cl in cname_raw:
|
||||
compression_literal = cl
|
||||
self.compression = compression_literal
|
||||
offset -= self._int_length
|
||||
|
||||
offset1 = offset + 16
|
||||
if self.U64:
|
||||
offset1 += 4
|
||||
|
||||
buf = self._read_bytes(offset1, self._lcp)
|
||||
compression_literal = buf.rstrip(b"\x00")
|
||||
if compression_literal == b"":
|
||||
self._lcs = 0
|
||||
offset1 = offset + 32
|
||||
if self.U64:
|
||||
offset1 += 4
|
||||
buf = self._read_bytes(offset1, self._lcp)
|
||||
self.creator_proc = buf[0 : self._lcp]
|
||||
elif compression_literal == const.rle_compression:
|
||||
offset1 = offset + 40
|
||||
if self.U64:
|
||||
offset1 += 4
|
||||
buf = self._read_bytes(offset1, self._lcp)
|
||||
self.creator_proc = buf[0 : self._lcp]
|
||||
elif self._lcs > 0:
|
||||
self._lcp = 0
|
||||
offset1 = offset + 16
|
||||
if self.U64:
|
||||
offset1 += 4
|
||||
buf = self._read_bytes(offset1, self._lcs)
|
||||
self.creator_proc = buf[0 : self._lcp]
|
||||
if hasattr(self, "creator_proc"):
|
||||
self.creator_proc = self._convert_header_text(self.creator_proc)
|
||||
|
||||
def _process_columnname_subheader(self, offset: int, length: int) -> None:
|
||||
int_len = self._int_length
|
||||
offset += int_len
|
||||
column_name_pointers_count = (length - 2 * int_len - 12) // 8
|
||||
for i in range(column_name_pointers_count):
|
||||
text_subheader = (
|
||||
offset
|
||||
+ const.column_name_pointer_length * (i + 1)
|
||||
+ const.column_name_text_subheader_offset
|
||||
)
|
||||
col_name_offset = (
|
||||
offset
|
||||
+ const.column_name_pointer_length * (i + 1)
|
||||
+ const.column_name_offset_offset
|
||||
)
|
||||
col_name_length = (
|
||||
offset
|
||||
+ const.column_name_pointer_length * (i + 1)
|
||||
+ const.column_name_length_offset
|
||||
)
|
||||
|
||||
idx = self._read_uint(
|
||||
text_subheader, const.column_name_text_subheader_length
|
||||
)
|
||||
col_offset = self._read_uint(
|
||||
col_name_offset, const.column_name_offset_length
|
||||
)
|
||||
col_len = self._read_uint(col_name_length, const.column_name_length_length)
|
||||
|
||||
name_raw = self.column_names_raw[idx]
|
||||
cname = name_raw[col_offset : col_offset + col_len]
|
||||
self.column_names.append(self._convert_header_text(cname))
|
||||
|
||||
def _process_columnattributes_subheader(self, offset: int, length: int) -> None:
|
||||
int_len = self._int_length
|
||||
column_attributes_vectors_count = (length - 2 * int_len - 12) // (int_len + 8)
|
||||
for i in range(column_attributes_vectors_count):
|
||||
col_data_offset = (
|
||||
offset + int_len + const.column_data_offset_offset + i * (int_len + 8)
|
||||
)
|
||||
col_data_len = (
|
||||
offset
|
||||
+ 2 * int_len
|
||||
+ const.column_data_length_offset
|
||||
+ i * (int_len + 8)
|
||||
)
|
||||
col_types = (
|
||||
offset + 2 * int_len + const.column_type_offset + i * (int_len + 8)
|
||||
)
|
||||
|
||||
x = self._read_uint(col_data_offset, int_len)
|
||||
self._column_data_offsets.append(x)
|
||||
|
||||
x = self._read_uint(col_data_len, const.column_data_length_length)
|
||||
self._column_data_lengths.append(x)
|
||||
|
||||
x = self._read_uint(col_types, const.column_type_length)
|
||||
self._column_types.append(b"d" if x == 1 else b"s")
|
||||
|
||||
def _process_columnlist_subheader(self, offset: int, length: int) -> None:
|
||||
# unknown purpose
|
||||
pass
|
||||
|
||||
def _process_format_subheader(self, offset: int, length: int) -> None:
|
||||
int_len = self._int_length
|
||||
text_subheader_format = (
|
||||
offset + const.column_format_text_subheader_index_offset + 3 * int_len
|
||||
)
|
||||
col_format_offset = offset + const.column_format_offset_offset + 3 * int_len
|
||||
col_format_len = offset + const.column_format_length_offset + 3 * int_len
|
||||
text_subheader_label = (
|
||||
offset + const.column_label_text_subheader_index_offset + 3 * int_len
|
||||
)
|
||||
col_label_offset = offset + const.column_label_offset_offset + 3 * int_len
|
||||
col_label_len = offset + const.column_label_length_offset + 3 * int_len
|
||||
|
||||
x = self._read_uint(
|
||||
text_subheader_format, const.column_format_text_subheader_index_length
|
||||
)
|
||||
format_idx = min(x, len(self.column_names_raw) - 1)
|
||||
|
||||
format_start = self._read_uint(
|
||||
col_format_offset, const.column_format_offset_length
|
||||
)
|
||||
format_len = self._read_uint(col_format_len, const.column_format_length_length)
|
||||
|
||||
label_idx = self._read_uint(
|
||||
text_subheader_label, const.column_label_text_subheader_index_length
|
||||
)
|
||||
label_idx = min(label_idx, len(self.column_names_raw) - 1)
|
||||
|
||||
label_start = self._read_uint(
|
||||
col_label_offset, const.column_label_offset_length
|
||||
)
|
||||
label_len = self._read_uint(col_label_len, const.column_label_length_length)
|
||||
|
||||
label_names = self.column_names_raw[label_idx]
|
||||
column_label = self._convert_header_text(
|
||||
label_names[label_start : label_start + label_len]
|
||||
)
|
||||
format_names = self.column_names_raw[format_idx]
|
||||
column_format = self._convert_header_text(
|
||||
format_names[format_start : format_start + format_len]
|
||||
)
|
||||
current_column_number = len(self.columns)
|
||||
|
||||
col = _Column(
|
||||
current_column_number,
|
||||
self.column_names[current_column_number],
|
||||
column_label,
|
||||
column_format,
|
||||
self._column_types[current_column_number],
|
||||
self._column_data_lengths[current_column_number],
|
||||
)
|
||||
|
||||
self.column_formats.append(column_format)
|
||||
self.columns.append(col)
|
||||
|
||||
def read(self, nrows: int | None = None) -> DataFrame:
|
||||
if (nrows is None) and (self.chunksize is not None):
|
||||
nrows = self.chunksize
|
||||
elif nrows is None:
|
||||
nrows = self.row_count
|
||||
|
||||
if len(self._column_types) == 0:
|
||||
self.close()
|
||||
raise EmptyDataError("No columns to parse from file")
|
||||
|
||||
if nrows > 0 and self._current_row_in_file_index >= self.row_count:
|
||||
return DataFrame()
|
||||
|
||||
nrows = min(nrows, self.row_count - self._current_row_in_file_index)
|
||||
|
||||
nd = self._column_types.count(b"d")
|
||||
ns = self._column_types.count(b"s")
|
||||
|
||||
self._string_chunk = np.empty((ns, nrows), dtype=object)
|
||||
self._byte_chunk = np.zeros((nd, 8 * nrows), dtype=np.uint8)
|
||||
|
||||
self._current_row_in_chunk_index = 0
|
||||
p = Parser(self)
|
||||
p.read(nrows)
|
||||
|
||||
rslt = self._chunk_to_dataframe()
|
||||
if self.index is not None:
|
||||
rslt = rslt.set_index(self.index)
|
||||
|
||||
return rslt
|
||||
|
||||
def _read_next_page(self):
|
||||
self._current_page_data_subheader_pointers = []
|
||||
self._cached_page = self._path_or_buf.read(self._page_length)
|
||||
if len(self._cached_page) <= 0:
|
||||
return True
|
||||
elif len(self._cached_page) != self._page_length:
|
||||
self.close()
|
||||
msg = (
|
||||
"failed to read complete page from file (read "
|
||||
f"{len(self._cached_page):d} of {self._page_length:d} bytes)"
|
||||
)
|
||||
raise ValueError(msg)
|
||||
|
||||
self._read_page_header()
|
||||
if self._current_page_type in const.page_meta_types:
|
||||
self._process_page_metadata()
|
||||
|
||||
if self._current_page_type not in const.page_meta_types + [
|
||||
const.page_data_type,
|
||||
const.page_mix_type,
|
||||
]:
|
||||
return self._read_next_page()
|
||||
|
||||
return False
|
||||
|
||||
def _chunk_to_dataframe(self) -> DataFrame:
|
||||
n = self._current_row_in_chunk_index
|
||||
m = self._current_row_in_file_index
|
||||
ix = range(m - n, m)
|
||||
rslt = {}
|
||||
|
||||
js, jb = 0, 0
|
||||
for j in range(self.column_count):
|
||||
name = self.column_names[j]
|
||||
|
||||
if self._column_types[j] == b"d":
|
||||
col_arr = self._byte_chunk[jb, :].view(dtype=self.byte_order + "d")
|
||||
rslt[name] = pd.Series(col_arr, dtype=np.float64, index=ix, copy=False)
|
||||
if self.convert_dates:
|
||||
if self.column_formats[j] in const.sas_date_formats:
|
||||
rslt[name] = _convert_datetimes(rslt[name], "d")
|
||||
elif self.column_formats[j] in const.sas_datetime_formats:
|
||||
rslt[name] = _convert_datetimes(rslt[name], "s")
|
||||
jb += 1
|
||||
elif self._column_types[j] == b"s":
|
||||
rslt[name] = pd.Series(self._string_chunk[js, :], index=ix, copy=False)
|
||||
if self.convert_text and (self.encoding is not None):
|
||||
rslt[name] = self._decode_string(rslt[name].str)
|
||||
js += 1
|
||||
else:
|
||||
self.close()
|
||||
raise ValueError(f"unknown column type {repr(self._column_types[j])}")
|
||||
|
||||
df = DataFrame(rslt, columns=self.column_names, index=ix, copy=False)
|
||||
return df
|
||||
|
||||
def _decode_string(self, b):
|
||||
return b.decode(self.encoding or self.default_encoding)
|
||||
|
||||
def _convert_header_text(self, b: bytes) -> str | bytes:
|
||||
if self.convert_header_text:
|
||||
return self._decode_string(b)
|
||||
else:
|
||||
return b
|
310
lib/python3.13/site-packages/pandas/io/sas/sas_constants.py
Normal file
310
lib/python3.13/site-packages/pandas/io/sas/sas_constants.py
Normal file
@ -0,0 +1,310 @@
|
||||
from __future__ import annotations
|
||||
|
||||
from typing import Final
|
||||
|
||||
magic: Final = (
|
||||
b"\x00\x00\x00\x00\x00\x00\x00\x00"
|
||||
b"\x00\x00\x00\x00\xc2\xea\x81\x60"
|
||||
b"\xb3\x14\x11\xcf\xbd\x92\x08\x00"
|
||||
b"\x09\xc7\x31\x8c\x18\x1f\x10\x11"
|
||||
)
|
||||
|
||||
align_1_checker_value: Final = b"3"
|
||||
align_1_offset: Final = 32
|
||||
align_1_length: Final = 1
|
||||
align_1_value: Final = 4
|
||||
u64_byte_checker_value: Final = b"3"
|
||||
align_2_offset: Final = 35
|
||||
align_2_length: Final = 1
|
||||
align_2_value: Final = 4
|
||||
endianness_offset: Final = 37
|
||||
endianness_length: Final = 1
|
||||
platform_offset: Final = 39
|
||||
platform_length: Final = 1
|
||||
encoding_offset: Final = 70
|
||||
encoding_length: Final = 1
|
||||
dataset_offset: Final = 92
|
||||
dataset_length: Final = 64
|
||||
file_type_offset: Final = 156
|
||||
file_type_length: Final = 8
|
||||
date_created_offset: Final = 164
|
||||
date_created_length: Final = 8
|
||||
date_modified_offset: Final = 172
|
||||
date_modified_length: Final = 8
|
||||
header_size_offset: Final = 196
|
||||
header_size_length: Final = 4
|
||||
page_size_offset: Final = 200
|
||||
page_size_length: Final = 4
|
||||
page_count_offset: Final = 204
|
||||
page_count_length: Final = 4
|
||||
sas_release_offset: Final = 216
|
||||
sas_release_length: Final = 8
|
||||
sas_server_type_offset: Final = 224
|
||||
sas_server_type_length: Final = 16
|
||||
os_version_number_offset: Final = 240
|
||||
os_version_number_length: Final = 16
|
||||
os_maker_offset: Final = 256
|
||||
os_maker_length: Final = 16
|
||||
os_name_offset: Final = 272
|
||||
os_name_length: Final = 16
|
||||
page_bit_offset_x86: Final = 16
|
||||
page_bit_offset_x64: Final = 32
|
||||
subheader_pointer_length_x86: Final = 12
|
||||
subheader_pointer_length_x64: Final = 24
|
||||
page_type_offset: Final = 0
|
||||
page_type_length: Final = 2
|
||||
block_count_offset: Final = 2
|
||||
block_count_length: Final = 2
|
||||
subheader_count_offset: Final = 4
|
||||
subheader_count_length: Final = 2
|
||||
page_type_mask: Final = 0x0F00
|
||||
# Keep "page_comp_type" bits
|
||||
page_type_mask2: Final = 0xF000 | page_type_mask
|
||||
page_meta_type: Final = 0x0000
|
||||
page_data_type: Final = 0x0100
|
||||
page_mix_type: Final = 0x0200
|
||||
page_amd_type: Final = 0x0400
|
||||
page_meta2_type: Final = 0x4000
|
||||
page_comp_type: Final = 0x9000
|
||||
page_meta_types: Final = [page_meta_type, page_meta2_type]
|
||||
subheader_pointers_offset: Final = 8
|
||||
truncated_subheader_id: Final = 1
|
||||
compressed_subheader_id: Final = 4
|
||||
compressed_subheader_type: Final = 1
|
||||
text_block_size_length: Final = 2
|
||||
row_length_offset_multiplier: Final = 5
|
||||
row_count_offset_multiplier: Final = 6
|
||||
col_count_p1_multiplier: Final = 9
|
||||
col_count_p2_multiplier: Final = 10
|
||||
row_count_on_mix_page_offset_multiplier: Final = 15
|
||||
column_name_pointer_length: Final = 8
|
||||
column_name_text_subheader_offset: Final = 0
|
||||
column_name_text_subheader_length: Final = 2
|
||||
column_name_offset_offset: Final = 2
|
||||
column_name_offset_length: Final = 2
|
||||
column_name_length_offset: Final = 4
|
||||
column_name_length_length: Final = 2
|
||||
column_data_offset_offset: Final = 8
|
||||
column_data_length_offset: Final = 8
|
||||
column_data_length_length: Final = 4
|
||||
column_type_offset: Final = 14
|
||||
column_type_length: Final = 1
|
||||
column_format_text_subheader_index_offset: Final = 22
|
||||
column_format_text_subheader_index_length: Final = 2
|
||||
column_format_offset_offset: Final = 24
|
||||
column_format_offset_length: Final = 2
|
||||
column_format_length_offset: Final = 26
|
||||
column_format_length_length: Final = 2
|
||||
column_label_text_subheader_index_offset: Final = 28
|
||||
column_label_text_subheader_index_length: Final = 2
|
||||
column_label_offset_offset: Final = 30
|
||||
column_label_offset_length: Final = 2
|
||||
column_label_length_offset: Final = 32
|
||||
column_label_length_length: Final = 2
|
||||
rle_compression: Final = b"SASYZCRL"
|
||||
rdc_compression: Final = b"SASYZCR2"
|
||||
|
||||
compression_literals: Final = [rle_compression, rdc_compression]
|
||||
|
||||
# Incomplete list of encodings, using SAS nomenclature:
|
||||
# https://support.sas.com/documentation/onlinedoc/dfdmstudio/2.6/dmpdmsug/Content/dfU_Encodings_SAS.html
|
||||
# corresponding to the Python documentation of standard encodings
|
||||
# https://docs.python.org/3/library/codecs.html#standard-encodings
|
||||
encoding_names: Final = {
|
||||
20: "utf-8",
|
||||
29: "latin1",
|
||||
30: "latin2",
|
||||
31: "latin3",
|
||||
32: "latin4",
|
||||
33: "cyrillic",
|
||||
34: "arabic",
|
||||
35: "greek",
|
||||
36: "hebrew",
|
||||
37: "latin5",
|
||||
38: "latin6",
|
||||
39: "cp874",
|
||||
40: "latin9",
|
||||
41: "cp437",
|
||||
42: "cp850",
|
||||
43: "cp852",
|
||||
44: "cp857",
|
||||
45: "cp858",
|
||||
46: "cp862",
|
||||
47: "cp864",
|
||||
48: "cp865",
|
||||
49: "cp866",
|
||||
50: "cp869",
|
||||
51: "cp874",
|
||||
# 52: "", # not found
|
||||
# 53: "", # not found
|
||||
# 54: "", # not found
|
||||
55: "cp720",
|
||||
56: "cp737",
|
||||
57: "cp775",
|
||||
58: "cp860",
|
||||
59: "cp863",
|
||||
60: "cp1250",
|
||||
61: "cp1251",
|
||||
62: "cp1252",
|
||||
63: "cp1253",
|
||||
64: "cp1254",
|
||||
65: "cp1255",
|
||||
66: "cp1256",
|
||||
67: "cp1257",
|
||||
68: "cp1258",
|
||||
118: "cp950",
|
||||
# 119: "", # not found
|
||||
123: "big5",
|
||||
125: "gb2312",
|
||||
126: "cp936",
|
||||
134: "euc_jp",
|
||||
136: "cp932",
|
||||
138: "shift_jis",
|
||||
140: "euc-kr",
|
||||
141: "cp949",
|
||||
227: "latin8",
|
||||
# 228: "", # not found
|
||||
# 229: "" # not found
|
||||
}
|
||||
|
||||
|
||||
class SASIndex:
|
||||
row_size_index: Final = 0
|
||||
column_size_index: Final = 1
|
||||
subheader_counts_index: Final = 2
|
||||
column_text_index: Final = 3
|
||||
column_name_index: Final = 4
|
||||
column_attributes_index: Final = 5
|
||||
format_and_label_index: Final = 6
|
||||
column_list_index: Final = 7
|
||||
data_subheader_index: Final = 8
|
||||
|
||||
|
||||
subheader_signature_to_index: Final = {
|
||||
b"\xF7\xF7\xF7\xF7": SASIndex.row_size_index,
|
||||
b"\x00\x00\x00\x00\xF7\xF7\xF7\xF7": SASIndex.row_size_index,
|
||||
b"\xF7\xF7\xF7\xF7\x00\x00\x00\x00": SASIndex.row_size_index,
|
||||
b"\xF7\xF7\xF7\xF7\xFF\xFF\xFB\xFE": SASIndex.row_size_index,
|
||||
b"\xF6\xF6\xF6\xF6": SASIndex.column_size_index,
|
||||
b"\x00\x00\x00\x00\xF6\xF6\xF6\xF6": SASIndex.column_size_index,
|
||||
b"\xF6\xF6\xF6\xF6\x00\x00\x00\x00": SASIndex.column_size_index,
|
||||
b"\xF6\xF6\xF6\xF6\xFF\xFF\xFB\xFE": SASIndex.column_size_index,
|
||||
b"\x00\xFC\xFF\xFF": SASIndex.subheader_counts_index,
|
||||
b"\xFF\xFF\xFC\x00": SASIndex.subheader_counts_index,
|
||||
b"\x00\xFC\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.subheader_counts_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFC\x00": SASIndex.subheader_counts_index,
|
||||
b"\xFD\xFF\xFF\xFF": SASIndex.column_text_index,
|
||||
b"\xFF\xFF\xFF\xFD": SASIndex.column_text_index,
|
||||
b"\xFD\xFF\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.column_text_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFD": SASIndex.column_text_index,
|
||||
b"\xFF\xFF\xFF\xFF": SASIndex.column_name_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.column_name_index,
|
||||
b"\xFC\xFF\xFF\xFF": SASIndex.column_attributes_index,
|
||||
b"\xFF\xFF\xFF\xFC": SASIndex.column_attributes_index,
|
||||
b"\xFC\xFF\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.column_attributes_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFC": SASIndex.column_attributes_index,
|
||||
b"\xFE\xFB\xFF\xFF": SASIndex.format_and_label_index,
|
||||
b"\xFF\xFF\xFB\xFE": SASIndex.format_and_label_index,
|
||||
b"\xFE\xFB\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.format_and_label_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFB\xFE": SASIndex.format_and_label_index,
|
||||
b"\xFE\xFF\xFF\xFF": SASIndex.column_list_index,
|
||||
b"\xFF\xFF\xFF\xFE": SASIndex.column_list_index,
|
||||
b"\xFE\xFF\xFF\xFF\xFF\xFF\xFF\xFF": SASIndex.column_list_index,
|
||||
b"\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFE": SASIndex.column_list_index,
|
||||
}
|
||||
|
||||
|
||||
# List of frequently used SAS date and datetime formats
|
||||
# http://support.sas.com/documentation/cdl/en/etsug/60372/HTML/default/viewer.htm#etsug_intervals_sect009.htm
|
||||
# https://github.com/epam/parso/blob/master/src/main/java/com/epam/parso/impl/SasFileConstants.java
|
||||
sas_date_formats: Final = (
|
||||
"DATE",
|
||||
"DAY",
|
||||
"DDMMYY",
|
||||
"DOWNAME",
|
||||
"JULDAY",
|
||||
"JULIAN",
|
||||
"MMDDYY",
|
||||
"MMYY",
|
||||
"MMYYC",
|
||||
"MMYYD",
|
||||
"MMYYP",
|
||||
"MMYYS",
|
||||
"MMYYN",
|
||||
"MONNAME",
|
||||
"MONTH",
|
||||
"MONYY",
|
||||
"QTR",
|
||||
"QTRR",
|
||||
"NENGO",
|
||||
"WEEKDATE",
|
||||
"WEEKDATX",
|
||||
"WEEKDAY",
|
||||
"WEEKV",
|
||||
"WORDDATE",
|
||||
"WORDDATX",
|
||||
"YEAR",
|
||||
"YYMM",
|
||||
"YYMMC",
|
||||
"YYMMD",
|
||||
"YYMMP",
|
||||
"YYMMS",
|
||||
"YYMMN",
|
||||
"YYMON",
|
||||
"YYMMDD",
|
||||
"YYQ",
|
||||
"YYQC",
|
||||
"YYQD",
|
||||
"YYQP",
|
||||
"YYQS",
|
||||
"YYQN",
|
||||
"YYQR",
|
||||
"YYQRC",
|
||||
"YYQRD",
|
||||
"YYQRP",
|
||||
"YYQRS",
|
||||
"YYQRN",
|
||||
"YYMMDDP",
|
||||
"YYMMDDC",
|
||||
"E8601DA",
|
||||
"YYMMDDN",
|
||||
"MMDDYYC",
|
||||
"MMDDYYS",
|
||||
"MMDDYYD",
|
||||
"YYMMDDS",
|
||||
"B8601DA",
|
||||
"DDMMYYN",
|
||||
"YYMMDDD",
|
||||
"DDMMYYB",
|
||||
"DDMMYYP",
|
||||
"MMDDYYP",
|
||||
"YYMMDDB",
|
||||
"MMDDYYN",
|
||||
"DDMMYYC",
|
||||
"DDMMYYD",
|
||||
"DDMMYYS",
|
||||
"MINGUO",
|
||||
)
|
||||
|
||||
sas_datetime_formats: Final = (
|
||||
"DATETIME",
|
||||
"DTWKDATX",
|
||||
"B8601DN",
|
||||
"B8601DT",
|
||||
"B8601DX",
|
||||
"B8601DZ",
|
||||
"B8601LX",
|
||||
"E8601DN",
|
||||
"E8601DT",
|
||||
"E8601DX",
|
||||
"E8601DZ",
|
||||
"E8601LX",
|
||||
"DATEAMPM",
|
||||
"DTDATE",
|
||||
"DTMONYY",
|
||||
"DTMONYY",
|
||||
"DTWKDATX",
|
||||
"DTYEAR",
|
||||
"TOD",
|
||||
"MDYAMPM",
|
||||
)
|
508
lib/python3.13/site-packages/pandas/io/sas/sas_xport.py
Normal file
508
lib/python3.13/site-packages/pandas/io/sas/sas_xport.py
Normal file
@ -0,0 +1,508 @@
|
||||
"""
|
||||
Read a SAS XPort format file into a Pandas DataFrame.
|
||||
|
||||
Based on code from Jack Cushman (github.com/jcushman/xport).
|
||||
|
||||
The file format is defined here:
|
||||
|
||||
https://support.sas.com/content/dam/SAS/support/en/technical-papers/record-layout-of-a-sas-version-5-or-6-data-set-in-sas-transport-xport-format.pdf
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
from collections import abc
|
||||
from datetime import datetime
|
||||
import struct
|
||||
from typing import TYPE_CHECKING
|
||||
import warnings
|
||||
|
||||
import numpy as np
|
||||
|
||||
from pandas.util._decorators import Appender
|
||||
from pandas.util._exceptions import find_stack_level
|
||||
|
||||
import pandas as pd
|
||||
|
||||
from pandas.io.common import get_handle
|
||||
from pandas.io.sas.sasreader import ReaderBase
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from pandas._typing import (
|
||||
CompressionOptions,
|
||||
DatetimeNaTType,
|
||||
FilePath,
|
||||
ReadBuffer,
|
||||
)
|
||||
_correct_line1 = (
|
||||
"HEADER RECORD*******LIBRARY HEADER RECORD!!!!!!!"
|
||||
"000000000000000000000000000000 "
|
||||
)
|
||||
_correct_header1 = (
|
||||
"HEADER RECORD*******MEMBER HEADER RECORD!!!!!!!000000000000000001600000000"
|
||||
)
|
||||
_correct_header2 = (
|
||||
"HEADER RECORD*******DSCRPTR HEADER RECORD!!!!!!!"
|
||||
"000000000000000000000000000000 "
|
||||
)
|
||||
_correct_obs_header = (
|
||||
"HEADER RECORD*******OBS HEADER RECORD!!!!!!!"
|
||||
"000000000000000000000000000000 "
|
||||
)
|
||||
_fieldkeys = [
|
||||
"ntype",
|
||||
"nhfun",
|
||||
"field_length",
|
||||
"nvar0",
|
||||
"name",
|
||||
"label",
|
||||
"nform",
|
||||
"nfl",
|
||||
"num_decimals",
|
||||
"nfj",
|
||||
"nfill",
|
||||
"niform",
|
||||
"nifl",
|
||||
"nifd",
|
||||
"npos",
|
||||
"_",
|
||||
]
|
||||
|
||||
|
||||
_base_params_doc = """\
|
||||
Parameters
|
||||
----------
|
||||
filepath_or_buffer : str or file-like object
|
||||
Path to SAS file or object implementing binary read method."""
|
||||
|
||||
_params2_doc = """\
|
||||
index : identifier of index column
|
||||
Identifier of column that should be used as index of the DataFrame.
|
||||
encoding : str
|
||||
Encoding for text data.
|
||||
chunksize : int
|
||||
Read file `chunksize` lines at a time, returns iterator."""
|
||||
|
||||
_format_params_doc = """\
|
||||
format : str
|
||||
File format, only `xport` is currently supported."""
|
||||
|
||||
_iterator_doc = """\
|
||||
iterator : bool, default False
|
||||
Return XportReader object for reading file incrementally."""
|
||||
|
||||
|
||||
_read_sas_doc = f"""Read a SAS file into a DataFrame.
|
||||
|
||||
{_base_params_doc}
|
||||
{_format_params_doc}
|
||||
{_params2_doc}
|
||||
{_iterator_doc}
|
||||
|
||||
Returns
|
||||
-------
|
||||
DataFrame or XportReader
|
||||
|
||||
Examples
|
||||
--------
|
||||
Read a SAS Xport file:
|
||||
|
||||
>>> df = pd.read_sas('filename.XPT')
|
||||
|
||||
Read a Xport file in 10,000 line chunks:
|
||||
|
||||
>>> itr = pd.read_sas('filename.XPT', chunksize=10000)
|
||||
>>> for chunk in itr:
|
||||
>>> do_something(chunk)
|
||||
|
||||
"""
|
||||
|
||||
_xport_reader_doc = f"""\
|
||||
Class for reading SAS Xport files.
|
||||
|
||||
{_base_params_doc}
|
||||
{_params2_doc}
|
||||
|
||||
Attributes
|
||||
----------
|
||||
member_info : list
|
||||
Contains information about the file
|
||||
fields : list
|
||||
Contains information about the variables in the file
|
||||
"""
|
||||
|
||||
_read_method_doc = """\
|
||||
Read observations from SAS Xport file, returning as data frame.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
nrows : int
|
||||
Number of rows to read from data file; if None, read whole
|
||||
file.
|
||||
|
||||
Returns
|
||||
-------
|
||||
A DataFrame.
|
||||
"""
|
||||
|
||||
|
||||
def _parse_date(datestr: str) -> DatetimeNaTType:
|
||||
"""Given a date in xport format, return Python date."""
|
||||
try:
|
||||
# e.g. "16FEB11:10:07:55"
|
||||
return datetime.strptime(datestr, "%d%b%y:%H:%M:%S")
|
||||
except ValueError:
|
||||
return pd.NaT
|
||||
|
||||
|
||||
def _split_line(s: str, parts):
|
||||
"""
|
||||
Parameters
|
||||
----------
|
||||
s: str
|
||||
Fixed-length string to split
|
||||
parts: list of (name, length) pairs
|
||||
Used to break up string, name '_' will be filtered from output.
|
||||
|
||||
Returns
|
||||
-------
|
||||
Dict of name:contents of string at given location.
|
||||
"""
|
||||
out = {}
|
||||
start = 0
|
||||
for name, length in parts:
|
||||
out[name] = s[start : start + length].strip()
|
||||
start += length
|
||||
del out["_"]
|
||||
return out
|
||||
|
||||
|
||||
def _handle_truncated_float_vec(vec, nbytes):
|
||||
# This feature is not well documented, but some SAS XPORT files
|
||||
# have 2-7 byte "truncated" floats. To read these truncated
|
||||
# floats, pad them with zeros on the right to make 8 byte floats.
|
||||
#
|
||||
# References:
|
||||
# https://github.com/jcushman/xport/pull/3
|
||||
# The R "foreign" library
|
||||
|
||||
if nbytes != 8:
|
||||
vec1 = np.zeros(len(vec), np.dtype("S8"))
|
||||
dtype = np.dtype(f"S{nbytes},S{8 - nbytes}")
|
||||
vec2 = vec1.view(dtype=dtype)
|
||||
vec2["f0"] = vec
|
||||
return vec2
|
||||
|
||||
return vec
|
||||
|
||||
|
||||
def _parse_float_vec(vec):
|
||||
"""
|
||||
Parse a vector of float values representing IBM 8 byte floats into
|
||||
native 8 byte floats.
|
||||
"""
|
||||
dtype = np.dtype(">u4,>u4")
|
||||
vec1 = vec.view(dtype=dtype)
|
||||
xport1 = vec1["f0"]
|
||||
xport2 = vec1["f1"]
|
||||
|
||||
# Start by setting first half of ieee number to first half of IBM
|
||||
# number sans exponent
|
||||
ieee1 = xport1 & 0x00FFFFFF
|
||||
|
||||
# The fraction bit to the left of the binary point in the ieee
|
||||
# format was set and the number was shifted 0, 1, 2, or 3
|
||||
# places. This will tell us how to adjust the ibm exponent to be a
|
||||
# power of 2 ieee exponent and how to shift the fraction bits to
|
||||
# restore the correct magnitude.
|
||||
shift = np.zeros(len(vec), dtype=np.uint8)
|
||||
shift[np.where(xport1 & 0x00200000)] = 1
|
||||
shift[np.where(xport1 & 0x00400000)] = 2
|
||||
shift[np.where(xport1 & 0x00800000)] = 3
|
||||
|
||||
# shift the ieee number down the correct number of places then
|
||||
# set the second half of the ieee number to be the second half
|
||||
# of the ibm number shifted appropriately, ored with the bits
|
||||
# from the first half that would have been shifted in if we
|
||||
# could shift a double. All we are worried about are the low
|
||||
# order 3 bits of the first half since we're only shifting by
|
||||
# 1, 2, or 3.
|
||||
ieee1 >>= shift
|
||||
ieee2 = (xport2 >> shift) | ((xport1 & 0x00000007) << (29 + (3 - shift)))
|
||||
|
||||
# clear the 1 bit to the left of the binary point
|
||||
ieee1 &= 0xFFEFFFFF
|
||||
|
||||
# set the exponent of the ieee number to be the actual exponent
|
||||
# plus the shift count + 1023. Or this into the first half of the
|
||||
# ieee number. The ibm exponent is excess 64 but is adjusted by 65
|
||||
# since during conversion to ibm format the exponent is
|
||||
# incremented by 1 and the fraction bits left 4 positions to the
|
||||
# right of the radix point. (had to add >> 24 because C treats &
|
||||
# 0x7f as 0x7f000000 and Python doesn't)
|
||||
ieee1 |= ((((((xport1 >> 24) & 0x7F) - 65) << 2) + shift + 1023) << 20) | (
|
||||
xport1 & 0x80000000
|
||||
)
|
||||
|
||||
ieee = np.empty((len(ieee1),), dtype=">u4,>u4")
|
||||
ieee["f0"] = ieee1
|
||||
ieee["f1"] = ieee2
|
||||
ieee = ieee.view(dtype=">f8")
|
||||
ieee = ieee.astype("f8")
|
||||
|
||||
return ieee
|
||||
|
||||
|
||||
class XportReader(ReaderBase, abc.Iterator):
|
||||
__doc__ = _xport_reader_doc
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
filepath_or_buffer: FilePath | ReadBuffer[bytes],
|
||||
index=None,
|
||||
encoding: str | None = "ISO-8859-1",
|
||||
chunksize: int | None = None,
|
||||
compression: CompressionOptions = "infer",
|
||||
) -> None:
|
||||
self._encoding = encoding
|
||||
self._lines_read = 0
|
||||
self._index = index
|
||||
self._chunksize = chunksize
|
||||
|
||||
self.handles = get_handle(
|
||||
filepath_or_buffer,
|
||||
"rb",
|
||||
encoding=encoding,
|
||||
is_text=False,
|
||||
compression=compression,
|
||||
)
|
||||
self.filepath_or_buffer = self.handles.handle
|
||||
|
||||
try:
|
||||
self._read_header()
|
||||
except Exception:
|
||||
self.close()
|
||||
raise
|
||||
|
||||
def close(self) -> None:
|
||||
self.handles.close()
|
||||
|
||||
def _get_row(self):
|
||||
return self.filepath_or_buffer.read(80).decode()
|
||||
|
||||
def _read_header(self) -> None:
|
||||
self.filepath_or_buffer.seek(0)
|
||||
|
||||
# read file header
|
||||
line1 = self._get_row()
|
||||
if line1 != _correct_line1:
|
||||
if "**COMPRESSED**" in line1:
|
||||
# this was created with the PROC CPORT method and can't be read
|
||||
# https://documentation.sas.com/doc/en/pgmsascdc/9.4_3.5/movefile/p1bm6aqp3fw4uin1hucwh718f6kp.htm
|
||||
raise ValueError(
|
||||
"Header record indicates a CPORT file, which is not readable."
|
||||
)
|
||||
raise ValueError("Header record is not an XPORT file.")
|
||||
|
||||
line2 = self._get_row()
|
||||
fif = [["prefix", 24], ["version", 8], ["OS", 8], ["_", 24], ["created", 16]]
|
||||
file_info = _split_line(line2, fif)
|
||||
if file_info["prefix"] != "SAS SAS SASLIB":
|
||||
raise ValueError("Header record has invalid prefix.")
|
||||
file_info["created"] = _parse_date(file_info["created"])
|
||||
self.file_info = file_info
|
||||
|
||||
line3 = self._get_row()
|
||||
file_info["modified"] = _parse_date(line3[:16])
|
||||
|
||||
# read member header
|
||||
header1 = self._get_row()
|
||||
header2 = self._get_row()
|
||||
headflag1 = header1.startswith(_correct_header1)
|
||||
headflag2 = header2 == _correct_header2
|
||||
if not (headflag1 and headflag2):
|
||||
raise ValueError("Member header not found")
|
||||
# usually 140, could be 135
|
||||
fieldnamelength = int(header1[-5:-2])
|
||||
|
||||
# member info
|
||||
mem = [
|
||||
["prefix", 8],
|
||||
["set_name", 8],
|
||||
["sasdata", 8],
|
||||
["version", 8],
|
||||
["OS", 8],
|
||||
["_", 24],
|
||||
["created", 16],
|
||||
]
|
||||
member_info = _split_line(self._get_row(), mem)
|
||||
mem = [["modified", 16], ["_", 16], ["label", 40], ["type", 8]]
|
||||
member_info.update(_split_line(self._get_row(), mem))
|
||||
member_info["modified"] = _parse_date(member_info["modified"])
|
||||
member_info["created"] = _parse_date(member_info["created"])
|
||||
self.member_info = member_info
|
||||
|
||||
# read field names
|
||||
types = {1: "numeric", 2: "char"}
|
||||
fieldcount = int(self._get_row()[54:58])
|
||||
datalength = fieldnamelength * fieldcount
|
||||
# round up to nearest 80
|
||||
if datalength % 80:
|
||||
datalength += 80 - datalength % 80
|
||||
fielddata = self.filepath_or_buffer.read(datalength)
|
||||
fields = []
|
||||
obs_length = 0
|
||||
while len(fielddata) >= fieldnamelength:
|
||||
# pull data for one field
|
||||
fieldbytes, fielddata = (
|
||||
fielddata[:fieldnamelength],
|
||||
fielddata[fieldnamelength:],
|
||||
)
|
||||
|
||||
# rest at end gets ignored, so if field is short, pad out
|
||||
# to match struct pattern below
|
||||
fieldbytes = fieldbytes.ljust(140)
|
||||
|
||||
fieldstruct = struct.unpack(">hhhh8s40s8shhh2s8shhl52s", fieldbytes)
|
||||
field = dict(zip(_fieldkeys, fieldstruct))
|
||||
del field["_"]
|
||||
field["ntype"] = types[field["ntype"]]
|
||||
fl = field["field_length"]
|
||||
if field["ntype"] == "numeric" and ((fl < 2) or (fl > 8)):
|
||||
msg = f"Floating field width {fl} is not between 2 and 8."
|
||||
raise TypeError(msg)
|
||||
|
||||
for k, v in field.items():
|
||||
try:
|
||||
field[k] = v.strip()
|
||||
except AttributeError:
|
||||
pass
|
||||
|
||||
obs_length += field["field_length"]
|
||||
fields += [field]
|
||||
|
||||
header = self._get_row()
|
||||
if not header == _correct_obs_header:
|
||||
raise ValueError("Observation header not found.")
|
||||
|
||||
self.fields = fields
|
||||
self.record_length = obs_length
|
||||
self.record_start = self.filepath_or_buffer.tell()
|
||||
|
||||
self.nobs = self._record_count()
|
||||
self.columns = [x["name"].decode() for x in self.fields]
|
||||
|
||||
# Setup the dtype.
|
||||
dtypel = [
|
||||
("s" + str(i), "S" + str(field["field_length"]))
|
||||
for i, field in enumerate(self.fields)
|
||||
]
|
||||
dtype = np.dtype(dtypel)
|
||||
self._dtype = dtype
|
||||
|
||||
def __next__(self) -> pd.DataFrame:
|
||||
return self.read(nrows=self._chunksize or 1)
|
||||
|
||||
def _record_count(self) -> int:
|
||||
"""
|
||||
Get number of records in file.
|
||||
|
||||
This is maybe suboptimal because we have to seek to the end of
|
||||
the file.
|
||||
|
||||
Side effect: returns file position to record_start.
|
||||
"""
|
||||
self.filepath_or_buffer.seek(0, 2)
|
||||
total_records_length = self.filepath_or_buffer.tell() - self.record_start
|
||||
|
||||
if total_records_length % 80 != 0:
|
||||
warnings.warn(
|
||||
"xport file may be corrupted.",
|
||||
stacklevel=find_stack_level(),
|
||||
)
|
||||
|
||||
if self.record_length > 80:
|
||||
self.filepath_or_buffer.seek(self.record_start)
|
||||
return total_records_length // self.record_length
|
||||
|
||||
self.filepath_or_buffer.seek(-80, 2)
|
||||
last_card_bytes = self.filepath_or_buffer.read(80)
|
||||
last_card = np.frombuffer(last_card_bytes, dtype=np.uint64)
|
||||
|
||||
# 8 byte blank
|
||||
ix = np.flatnonzero(last_card == 2314885530818453536)
|
||||
|
||||
if len(ix) == 0:
|
||||
tail_pad = 0
|
||||
else:
|
||||
tail_pad = 8 * len(ix)
|
||||
|
||||
self.filepath_or_buffer.seek(self.record_start)
|
||||
|
||||
return (total_records_length - tail_pad) // self.record_length
|
||||
|
||||
def get_chunk(self, size: int | None = None) -> pd.DataFrame:
|
||||
"""
|
||||
Reads lines from Xport file and returns as dataframe
|
||||
|
||||
Parameters
|
||||
----------
|
||||
size : int, defaults to None
|
||||
Number of lines to read. If None, reads whole file.
|
||||
|
||||
Returns
|
||||
-------
|
||||
DataFrame
|
||||
"""
|
||||
if size is None:
|
||||
size = self._chunksize
|
||||
return self.read(nrows=size)
|
||||
|
||||
def _missing_double(self, vec):
|
||||
v = vec.view(dtype="u1,u1,u2,u4")
|
||||
miss = (v["f1"] == 0) & (v["f2"] == 0) & (v["f3"] == 0)
|
||||
miss1 = (
|
||||
((v["f0"] >= 0x41) & (v["f0"] <= 0x5A))
|
||||
| (v["f0"] == 0x5F)
|
||||
| (v["f0"] == 0x2E)
|
||||
)
|
||||
miss &= miss1
|
||||
return miss
|
||||
|
||||
@Appender(_read_method_doc)
|
||||
def read(self, nrows: int | None = None) -> pd.DataFrame:
|
||||
if nrows is None:
|
||||
nrows = self.nobs
|
||||
|
||||
read_lines = min(nrows, self.nobs - self._lines_read)
|
||||
read_len = read_lines * self.record_length
|
||||
if read_len <= 0:
|
||||
self.close()
|
||||
raise StopIteration
|
||||
raw = self.filepath_or_buffer.read(read_len)
|
||||
data = np.frombuffer(raw, dtype=self._dtype, count=read_lines)
|
||||
|
||||
df_data = {}
|
||||
for j, x in enumerate(self.columns):
|
||||
vec = data["s" + str(j)]
|
||||
ntype = self.fields[j]["ntype"]
|
||||
if ntype == "numeric":
|
||||
vec = _handle_truncated_float_vec(vec, self.fields[j]["field_length"])
|
||||
miss = self._missing_double(vec)
|
||||
v = _parse_float_vec(vec)
|
||||
v[miss] = np.nan
|
||||
elif self.fields[j]["ntype"] == "char":
|
||||
v = [y.rstrip() for y in vec]
|
||||
|
||||
if self._encoding is not None:
|
||||
v = [y.decode(self._encoding) for y in v]
|
||||
|
||||
df_data.update({x: v})
|
||||
df = pd.DataFrame(df_data)
|
||||
|
||||
if self._index is None:
|
||||
df.index = pd.Index(range(self._lines_read, self._lines_read + read_lines))
|
||||
else:
|
||||
df = df.set_index(self._index)
|
||||
|
||||
self._lines_read += read_lines
|
||||
|
||||
return df
|
178
lib/python3.13/site-packages/pandas/io/sas/sasreader.py
Normal file
178
lib/python3.13/site-packages/pandas/io/sas/sasreader.py
Normal file
@ -0,0 +1,178 @@
|
||||
"""
|
||||
Read SAS sas7bdat or xport files.
|
||||
"""
|
||||
from __future__ import annotations
|
||||
|
||||
from abc import (
|
||||
ABC,
|
||||
abstractmethod,
|
||||
)
|
||||
from typing import (
|
||||
TYPE_CHECKING,
|
||||
overload,
|
||||
)
|
||||
|
||||
from pandas.util._decorators import doc
|
||||
|
||||
from pandas.core.shared_docs import _shared_docs
|
||||
|
||||
from pandas.io.common import stringify_path
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from collections.abc import Hashable
|
||||
from types import TracebackType
|
||||
|
||||
from pandas._typing import (
|
||||
CompressionOptions,
|
||||
FilePath,
|
||||
ReadBuffer,
|
||||
Self,
|
||||
)
|
||||
|
||||
from pandas import DataFrame
|
||||
|
||||
|
||||
class ReaderBase(ABC):
|
||||
"""
|
||||
Protocol for XportReader and SAS7BDATReader classes.
|
||||
"""
|
||||
|
||||
@abstractmethod
|
||||
def read(self, nrows: int | None = None) -> DataFrame:
|
||||
...
|
||||
|
||||
@abstractmethod
|
||||
def close(self) -> None:
|
||||
...
|
||||
|
||||
def __enter__(self) -> Self:
|
||||
return self
|
||||
|
||||
def __exit__(
|
||||
self,
|
||||
exc_type: type[BaseException] | None,
|
||||
exc_value: BaseException | None,
|
||||
traceback: TracebackType | None,
|
||||
) -> None:
|
||||
self.close()
|
||||
|
||||
|
||||
@overload
|
||||
def read_sas(
|
||||
filepath_or_buffer: FilePath | ReadBuffer[bytes],
|
||||
*,
|
||||
format: str | None = ...,
|
||||
index: Hashable | None = ...,
|
||||
encoding: str | None = ...,
|
||||
chunksize: int = ...,
|
||||
iterator: bool = ...,
|
||||
compression: CompressionOptions = ...,
|
||||
) -> ReaderBase:
|
||||
...
|
||||
|
||||
|
||||
@overload
|
||||
def read_sas(
|
||||
filepath_or_buffer: FilePath | ReadBuffer[bytes],
|
||||
*,
|
||||
format: str | None = ...,
|
||||
index: Hashable | None = ...,
|
||||
encoding: str | None = ...,
|
||||
chunksize: None = ...,
|
||||
iterator: bool = ...,
|
||||
compression: CompressionOptions = ...,
|
||||
) -> DataFrame | ReaderBase:
|
||||
...
|
||||
|
||||
|
||||
@doc(decompression_options=_shared_docs["decompression_options"] % "filepath_or_buffer")
|
||||
def read_sas(
|
||||
filepath_or_buffer: FilePath | ReadBuffer[bytes],
|
||||
*,
|
||||
format: str | None = None,
|
||||
index: Hashable | None = None,
|
||||
encoding: str | None = None,
|
||||
chunksize: int | None = None,
|
||||
iterator: bool = False,
|
||||
compression: CompressionOptions = "infer",
|
||||
) -> DataFrame | ReaderBase:
|
||||
"""
|
||||
Read SAS files stored as either XPORT or SAS7BDAT format files.
|
||||
|
||||
Parameters
|
||||
----------
|
||||
filepath_or_buffer : str, path object, or file-like object
|
||||
String, path object (implementing ``os.PathLike[str]``), or file-like
|
||||
object implementing a binary ``read()`` function. The string could be a URL.
|
||||
Valid URL schemes include http, ftp, s3, and file. For file URLs, a host is
|
||||
expected. A local file could be:
|
||||
``file://localhost/path/to/table.sas7bdat``.
|
||||
format : str {{'xport', 'sas7bdat'}} or None
|
||||
If None, file format is inferred from file extension. If 'xport' or
|
||||
'sas7bdat', uses the corresponding format.
|
||||
index : identifier of index column, defaults to None
|
||||
Identifier of column that should be used as index of the DataFrame.
|
||||
encoding : str, default is None
|
||||
Encoding for text data. If None, text data are stored as raw bytes.
|
||||
chunksize : int
|
||||
Read file `chunksize` lines at a time, returns iterator.
|
||||
iterator : bool, defaults to False
|
||||
If True, returns an iterator for reading the file incrementally.
|
||||
{decompression_options}
|
||||
|
||||
Returns
|
||||
-------
|
||||
DataFrame if iterator=False and chunksize=None, else SAS7BDATReader
|
||||
or XportReader
|
||||
|
||||
Examples
|
||||
--------
|
||||
>>> df = pd.read_sas("sas_data.sas7bdat") # doctest: +SKIP
|
||||
"""
|
||||
if format is None:
|
||||
buffer_error_msg = (
|
||||
"If this is a buffer object rather "
|
||||
"than a string name, you must specify a format string"
|
||||
)
|
||||
filepath_or_buffer = stringify_path(filepath_or_buffer)
|
||||
if not isinstance(filepath_or_buffer, str):
|
||||
raise ValueError(buffer_error_msg)
|
||||
fname = filepath_or_buffer.lower()
|
||||
if ".xpt" in fname:
|
||||
format = "xport"
|
||||
elif ".sas7bdat" in fname:
|
||||
format = "sas7bdat"
|
||||
else:
|
||||
raise ValueError(
|
||||
f"unable to infer format of SAS file from filename: {repr(fname)}"
|
||||
)
|
||||
|
||||
reader: ReaderBase
|
||||
if format.lower() == "xport":
|
||||
from pandas.io.sas.sas_xport import XportReader
|
||||
|
||||
reader = XportReader(
|
||||
filepath_or_buffer,
|
||||
index=index,
|
||||
encoding=encoding,
|
||||
chunksize=chunksize,
|
||||
compression=compression,
|
||||
)
|
||||
elif format.lower() == "sas7bdat":
|
||||
from pandas.io.sas.sas7bdat import SAS7BDATReader
|
||||
|
||||
reader = SAS7BDATReader(
|
||||
filepath_or_buffer,
|
||||
index=index,
|
||||
encoding=encoding,
|
||||
chunksize=chunksize,
|
||||
compression=compression,
|
||||
)
|
||||
else:
|
||||
raise ValueError("unknown SAS format")
|
||||
|
||||
if iterator or chunksize:
|
||||
return reader
|
||||
|
||||
with reader:
|
||||
return reader.read()
|
Reference in New Issue
Block a user