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)