I'm working in Python with MongoDB trying to save an array of floats tightly.
I can Create and store correctly *
but I CANNOT RETRIEVE THE DATA IN A USABLE FORMAT.
>>> import random, array, pymongo
>>> from bson.binary import Binary as BsonBinary
>>> con = pymongo.Connection('localhost', 27017)
>>> mm = con['testDatabase']
>>> vals = [random.random() *100 for x in range(1, 5)]
>>> vals
[2.9962593, 64.5582810776, 32.3781311717, 82.0606953423]
>>> varray = array.array('f', vals)
>>> varray
array('f', [2.9962593, 64.5582810776, 32.3781311717, 82.0606953423])
>>> vstring = varray.tostring()
>>> vstring
'xb7xc2?@xd7x1dx81B5x83x01Bx13x1fxa4B'
>>> vbson = BsonBinary(vstring, 5)
>>> vbson
Binary('xb7xc2?@xd7x1dx81B5x83x01Bx13x1fxa4B', 5)
>>> doc1 = { 'something': 1 , 'else' : vbson}
>>> doc1
{'something': 1, 'else': Binary('xb7xc2?@xd7x1dx81B5x83x01Bx13x1fxa4B', 5)}
>>> mm.test1.insert(doc1)
ObjectID('530f7af1d809d80d3db1f635')
>>> gotdoc = mm.test1.find_one()
>>> gotdoc
{u'_id': ObjectId('530f7af1d809d80d3db1f635'), u'something': 3, u'else': Binary('xb7xc2?@xd7x1dx81B5x83x01Bx13x1fxa4B', 5)}
>>> gotfield = gotdoc['else']
>>> gotfield
Binary('xb7xc2?@xd7x1dx81B5x83x01Bx13x1fxa4B', 5)
>>> from bson import BSON
>>> BSON.decode(gotfield)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: unbound method decode() must be called with BSON instance as first argument (got Binary instance instead)
>>> gotfield.decode()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xb7 in position 0: ordinal not in range(128)
>>>
Once I get my Python string back, I can get my array of random floats back. But how?
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