def unconvert(values, dtype, compress=None):
as_is_ext = isinstance(values, ExtType) and values.code == 0
if as_is_ext:
values = values.data
if is_categorical_dtype(dtype):
return values
elif is_object_dtype(dtype):
return np.array(values, dtype=object)
dtype = pandas_dtype(dtype).base
if not as_is_ext:
values = values.encode("latin1")
if compress:
if compress == "zlib":
zlib = import_optional_dependency(
"zlib", extra="zlib is required when `compress='zlib'`."
)
decompress = zlib.decompress
elif compress == "blosc":
blosc = import_optional_dependency(
"blosc", extra="zlib is required when `compress='blosc'`."
)
decompress = blosc.decompress
else:
raise ValueError("compress must be one of 'zlib' or 'blosc'")
try:
return np.frombuffer(
_move_into_mutable_buffer(decompress(values)), dtype=dtype
)
except _BadMove as e:
# Pull the decompressed data off of the `_BadMove` exception.
# We don't just store this in the locals because we want to
# minimize the risk of giving users access to a `bytes` object
# whose data is also given to a mutable buffer.
values = e.args[0]
if len(values) > 1:
# The empty string and single characters are memoized in many
# string creating functions in the capi. This case should not
# warn even though we need to make a copy because we are only
# copying at most 1 byte.
warnings.warn(
"copying data after decompressing; this may mean that"
" decompress is caching its result",
PerformanceWarning,
)
# fall through to copying `np.fromstring`
# Copy the bytes into a numpy array.
buf = np.frombuffer(values, dtype=dtype)
buf = buf.copy() # required to not mutate the original data
buf.flags.writeable = True
return buf
def unconvert(values, dtype, compress=None):
as_is_ext = isinstance(values, ExtType) and values.code == 0
if as_is_ext:
values = values.data
if is_categorical_dtype(dtype):
return values
elif is_object_dtype(dtype):
return np.array(values, dtype=object)
dtype = pandas_dtype(dtype).base
if not as_is_ext:
values = values.encode('latin1')
if compress:
if compress == u'zlib':
_check_zlib()
decompress = zlib.decompress
elif compress == u'blosc':
_check_blosc()
decompress = blosc.decompress
else:
raise ValueError("compress must be one of 'zlib' or 'blosc'")
try:
return np.frombuffer(
_move_into_mutable_buffer(decompress(values)),
dtype=dtype,
)
except _BadMove as e:
# Pull the decompressed data off of the `_BadMove` exception.
# We don't just store this in the locals because we want to
# minimize the risk of giving users access to a `bytes` object
# whose data is also given to a mutable buffer.
values = e.args[0]
if len(values) > 1:
# The empty string and single characters are memoized in many
# string creating functions in the capi. This case should not
# warn even though we need to make a copy because we are only
# copying at most 1 byte.
warnings.warn(
'copying data after decompressing; this may mean that'
' decompress is caching its result',
PerformanceWarning,
)
# fall through to copying `np.fromstring`
# Copy the bytes into a numpy array.
buf = np.frombuffer(values, dtype=dtype)
buf = buf.copy() # required to not mutate the original data
buf.flags.writeable = True
return buf
def unconvert(values, dtype, compress=None):
as_is_ext = isinstance(values, ExtType) and values.code == 0
if as_is_ext:
values = values.data
if is_categorical_dtype(dtype):
return values
elif is_object_dtype(dtype):
return np.array(values, dtype=object)
dtype = pandas_dtype(dtype).base
if not as_is_ext:
values = values.encode('latin1')
if compress:
if compress == u'zlib':
_check_zlib()
decompress = zlib.decompress
elif compress == u'blosc':
_check_blosc()
decompress = blosc.decompress
else:
raise ValueError("compress must be one of 'zlib' or 'blosc'")
try:
return np.frombuffer(
_move_into_mutable_buffer(decompress(values)),
dtype=dtype,
)
except _BadMove as e:
# Pull the decompressed data off of the `_BadMove` exception.
# We don't just store this in the locals because we want to
# minimize the risk of giving users access to a `bytes` object
# whose data is also given to a mutable buffer.
values = e.args[0]
if len(values) > 1:
# The empty string and single characters are memoized in many
# string creating functions in the capi. This case should not
# warn even though we need to make a copy because we are only
# copying at most 1 byte.
warnings.warn(
'copying data after decompressing; this may mean that'
' decompress is caching its result',
PerformanceWarning,
)
# fall through to copying `np.fromstring`
# Copy the string into a numpy array.
return np.fromstring(values, dtype=dtype)
