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What is the difference between NaN and None?
I am reading two columns of a csv file using pandas readcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead ...
How can I write to the console in PHP?
... Firefox you can use an extension called FirePHP which enables the logging and dumping of information from your PHP applications to the console. This is an addon to the awesome web development extension Firebug.
http://www.studytrails.com/blog/using-firephp-in-firefox-to-debug-php/
Chrome
Howev...
How can I define a composite primary key in SQL?
...rID)
);
The pair (QuestionID,MemberID) must then be unique for the table and neither value can be NULL. If you do a query like this:
SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because...
Is it possible to Turn page programmatically in UIPageViewController?
... can use it to go to other pages.
Wonder why viewControllers is an array, and not a single view controller?
That's because a page view controller could have a "spine" (like in iBooks), displaying 2 pages of content at a time. If you display 1 page of content at a time, then just pass in a 1-elemen...
How to set the margin or padding as percentage of height of parent container?
...
The fix is that yes, vertical padding and margin are relative to width, but top and bottom aren't.
So just place a div inside another, and in the inner div, use something like top:50% (remember position matters if it still doesn't work)
...
DateTime.ToString() format that can be used in a filename or extension?
...d but most of the DateTime methods I've tried output something with spaces and slashes. For instance:
8 Answers
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Error java.lang.OutOfMemoryError: GC overhead limit exceeded
...n excessive amount of time (by default 98% of all CPU time of the process) and recovers very little memory in each run (by default 2% of the heap).
This effectively means that your program stops doing any progress and is busy running only the garbage collection at all time.
To prevent your applica...
Is SQL or even TSQL Turing Complete?
...e programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allows you to crea...
Replacing .NET WebBrowser control with a better browser, like Chrome?
...ject I started a while back that thankfully got picked up by the community and turned into something wonderful.
The project wraps the Chromium Embedded Framework and has been used in a number of major projects including Rdio's Windows client, Facebook Messenger for Windows and Github for Windows.
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Assign one struct to another in C
...re an issue than it is for assignment of the built in types, like integers and doubles - assignment is not an atomic operation for these either.
– anon
Feb 20 '10 at 13:58
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