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How to add an extra column to a NumPy array
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b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstack((a,np.zeros((a.shape[0],1))))
10000 loops, best of 3: 19.6 us per loop
In [27]: %timeit b = np.zeros((a.shape[0],a.shape[1]+1)); b[:,:-1] = a
100000 loops, best of ...
Foreign keys in mongo?
...{group:"phones"})
> db.foo.find()
{ "_id" : ObjectId("4df6539ae90592692ccc9940"), "group" : "phones" }
{ "_id" : ObjectId("4df6540fe90592692ccc9941"), "group" : "phones" }
>db.foo.find({'_id':ObjectId("4df6539ae90592692ccc9940")})
{ "_id" : ObjectId("4df6539ae90592692ccc9940...
How to find list of possible words from a letter matrix [Boggle Solver]
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145
+150
My answ...
SQL Server - Create a copy of a database table and place it in the same database?
...ther
– Simon Green
Oct 6 '15 at 19:04
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How are Python's Built In Dictionaries Implemented?
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When a new dict is initialized it starts with 8 slots. (see dictobject.h:49)
When adding entries to the table, we start with some slot, i, that is based on the hash of the key. CPython initially uses i = hash(key) & mask (where mask = PyDictMINSIZE - 1, but that's not really important). Just ...
How to flush output of print function?
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edited Sep 23 '19 at 4:26
Boris
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answered Oc...
How to compile a static library in Linux?
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answered Apr 29 '10 at 4:10
Matthew FlaschenMatthew Flaschen
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How do I unit test web api action method when it returns IHttpActionResult?
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answered Nov 12 '13 at 18:46
Kiran ChallaKiran Challa
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_DEBUG vs NDEBUG
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ChristophChristoph
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