[Numpy-discussion] attributes of scalar types - e.g. numpy.int32.itemsize

Travis Oliphant oliphant.travis at ieee.org
Fri Aug 18 17:25:47 CDT 2006


Sebastian Haase wrote:
> On Friday 18 August 2006 11:38, Travis Oliphant wrote:
>   
>> Sebastian Haase wrote:
>>     
>>> Hi,
>>> array dtype descriptors have an attribute itemsize  that gives the total
>>> number of bytes required for an item of that dtype.
>>>
>>> Scalar types, like  numy.int32, also have that attribute,
>>> but it returns "something else" - don't know what:
>>>
>>>
>>> Furthermore there are *lot's*  of more attributes to a scalar dtype, e.g.
>>>       
>> The scalar types are actual Python types (classes) whereas the dtype
>> objects are instances.
>>
>> The attributes you are seeing of the typeobject are very useful when you
>> have an instance of that type.
>>
>> With numpy.int32.itemsize you are doing the equivalent of
>> numpy.dtype.itemsize
>>     
>
> but why then do I not get the result 4 ?
>   
Because it's not a "class" attribute, it's an instance attribute.

What does numpy.dtype.itemsize give you?

-Travis





More information about the Numpy-discussion mailing list