How can i check type of object?

Question

Possible Duplicate:
Python - Determine the type of an object?

I want 'complex' to be printed, but nothing happend, why? How to do this right?

>>> c = (5+3j)
>>> type(c)
<type 'complex'>
>>> if type(c) == 'complex': print 'complex'
... 
>>>

Mark Byers · Accepted Answer · 2011-12-04T10:20:53.877

5

You can use isinstance:

if isinstance(c, complex):

From the documentation:

Return true if the object argument is an instance of the classinfo argument, or of a (direct, indirect or virtual) subclass thereof. Also return true if classinfo is a type object (new-style class) and object is an object of that type or of a (direct, indirect or virtual) subclass thereof.

edited Dec 04 '11 at 10:20

answered Dec 04 '11 at 10:14

Mark Byers

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i start from python tutorial, but have some questions before they are explained, thank You – Cadilac Dec 04 '11 at 10:23
1

Before using this everywhere, you might wish to read [`isinstance()` considered harmful](http://www.canonical.org/~kragen/isinstance/). – Mark Byers Dec 04 '11 at 10:31
if this is important i will read it – Cadilac Dec 04 '11 at 10:40

score 2 · Answer 2 · answered Dec 04 '11 at 10:14

2

Try if isinstance(c,complex): print 'complex'

answered Dec 04 '11 at 10:14

Abhijit

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score 2 · Answer 3 · answered Dec 04 '11 at 10:15

2

>>> c = 5+3j
>>> c
(5+3j)
>>> type(c)
<type 'complex'>
>>> complex
<type 'complex'>
>>> type(c) == complex
True
>>> isinstance(c, complex)
True
>>>

type(c) == complex would mean "this is definitely an instance of complex, not some subclass". isinstance(c, complex) would include subclasses.

answered Dec 04 '11 at 10:15

cHao

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good to know about this, thank You – Cadilac Dec 04 '11 at 10:22

How can i check type of object?

3 Answers3