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Get the first element of each tuple in a list in Python [duplicate]
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Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
Maximum number of records in a MySQL database table
... The poster is not asking about numeric or any other data types. . I really do not understand how this can be flagged as a correct answer. Though I must admit that the question is ambiguous we should distinguish between PK data type and maximum number of rows for a table.
–...
List comprehension vs map
...ing map() over list comprehension or vice versa? Is either of them generally more efficient or considered generally more pythonic than the other?
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In Python how should I test if a variable is None, True or False
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a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none
– wesm
Apr 3 '15 at 21:06
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Why compile Python code?
...ou invoke with python main.py is recompiled every time you run the script. All imported scripts will be compiled and stored on the disk.
Important addition by Ben Blank:
It's worth noting that while running a
compiled script has a faster startup
time (as it doesn't need to be
compiled), i...
How to scroll to specific item using jQuery?
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element.scrollIntoView() - that is all that is required. Animation is standardised. See developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoView
– WickyNilliams
Feb 26 '16 at 11:46
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wkhtmltopdf: cannot connect to X server
...ble, so no need to make the wrapper script.
– jeffery_the_wind
Mar 13 '12 at 13:43
it worked for me.. in some situatio...
Mockito + PowerMock LinkageError while mocking system class
...nd any way to do this. We have hundreds of tests ... i can not adjust them all.
– Frederic Leitenberger
Jul 11 '17 at 18:01
1
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back button callback in navigationController in iOS
...elegate if it should pop the top UINavigationItem by calling navigationBar(_:shouldPop:). UINavigationController actually implement this, but it doesn't publicly declare that it adopts UINavigationBarDelegate (why!?). To intercept this event, create a subclass of UINavigationController, declare its ...
Email address validation using ASP.NET MVC data type attributes
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Validating email addresses with regex is usually a terrible idea... but if you must, there's an excellent reference here.. regular-expressions.info/email.html
– Molomby
Jul 23 '14 at 4:18
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