On 2/22/2015 12:53 PM, LJ wrote:
Hi everyone. Quick question here. Lets suppose if have the
following numpy array:
b=np.array([[0]*2]*3)
and then:
id(b[0])
45855552
id(b[1])
45857512
id(b[2])
45855552
Please correct me if I am wrong,
You are, as other explained
> but according to this b[2] and b[0] are the same object.
b[0] is b[2]
False
Any clarification is much appreciated.
In Python, 'two' objects can only be the same thing if they exist
simultaneously. Retry your experiment with simultaneous objects.
>>> b0 = b[0]
>>> b1 = b[1]
>>> b2 = b[2] # etc.
The three objects will have different ids. The mail purpose of the id
function is to text properties of a particular implementation. It also
has uses with ctypes. Beginners should generally ignore it, and
certainly not touch it until reading and understanding its doc. The
main use for 'is' is for 'is None' comparison.
--
Terry Jan Reedy
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