MsgPack

class numcodecs.msgpacks.MsgPack(use_single_float=False, use_bin_type=True, raw=False)[source]

Codec to encode data as msgpacked bytes. Useful for encoding an array of Python objects.

Changed in version 0.6: The encoding format has been changed to include the array shape in the encoded data, which ensures that all object arrays can be correctly encoded and decoded.

Parameters:
use_single_floatbool, optional

Use single precision float type for float.

use_bin_typebool, optional

Use bin type introduced in msgpack spec 2.0 for bytes. It also enables str8 type for unicode.

rawbool, optional

If true, unpack msgpack raw to Python bytes. Otherwise, unpack to Python str by decoding with UTF-8 encoding.

Notes

Requires msgpack to be installed.

Examples

>>> import numcodecs
>>> import numpy as np
>>> x = np.array(['foo', 'bar', 'baz'], dtype='object')
>>> codec = numcodecs.MsgPack()
>>> codec.decode(codec.encode(x))
array(['foo', 'bar', 'baz'], dtype=object)
codec_id = 'msgpack2'

Codec identifier.

encode(buf)[source]

Encode data in buf.

Parameters:
bufbuffer-like

Data to be encoded. May be any object supporting the new-style buffer protocol.

Returns:
encbuffer-like

Encoded data. May be any object supporting the new-style buffer protocol.

decode(buf, out=None)[source]

Decode data in buf.

Parameters:
bufbuffer-like

Encoded data. May be any object supporting the new-style buffer protocol.

outbuffer-like, optional

Writeable buffer to store decoded data. N.B. if provided, this buffer must be exactly the right size to store the decoded data.

Returns:
decbuffer-like

Decoded data. May be any object supporting the new-style buffer protocol.

get_config()[source]

Return a dictionary holding configuration parameters for this codec. Must include an ‘id’ field with the codec identifier. All values must be compatible with JSON encoding.

classmethod from_config(config)

Instantiate codec from a configuration object.