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Omitting the first line from any Linux command output
...red Sep 6 '11 at 10:41
Jeff FerlandJeff Ferland
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What are metaclasses in Python?
In Python, what are metaclasses and what do we use them for?
22 Answers
22
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Get first day of week in SQL Server
..., storing the aggregated date as the first day of the week. However, the standard technique I use for rounding off dates does not appear to work correctly with weeks (though it does for days, months, years, quarters and any other timeframe I've applied it to).
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How good is Java's UUID.randomUUID?
I know that randomized UUIDs have a very, very, very low probability for collision in theory, but I am wondering, in practice, how good Java's randomUUID() is in terms of not having collision? Does anybody have any experience to share?
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Java compile speed vs Scala compile speed
I've been programming in Scala for a while and I like it but one thing I'm annoyed by is the time it takes to compile programs. It's seems like a small thing but with Java I could make small changes to my program, click the run button in netbeans, and BOOM, it's running, and over time compiling in ...
Is there a regular expression to detect a valid regular expression?
...group start
(?:
(?:[^?+*{}()[\]\\|]+ # literals and ^, $
| \\. # escaped characters
| \[ (?: \^?\\. | \^[^\\] | [^\\^] ) # character classes
(?: [^\]\\]+ | \\. )* \]
| \( (?:\?[:=!]|\?<[=!]|\?>)? (?1)?? ...
Is a Java string really immutable?
...hange the lookup table used in Integer autoboxing etc.
Now, the reason s1 and s2 change value, is that they both refer to the same interned string. The compiler does this (as mentioned by other answers).
The reason s3 does not was actually a bit surprising to me, as I thought it would share the v...
How to make a flat list out of list of lists?
...for item in sublist]
As evidence, you can use the timeit module in the standard library:
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
How to JSON serialize sets?
I have a Python set that contains objects with __hash__ and __eq__ methods in order to make certain no duplicates are included in the collection.
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Tablix: Repeat header rows on each page not working - Report Builder 3.0
...porting Services does not recognize which textboxes are the column headers and setting RepeatColumnHeaders property to True doesn't work.
Instead, you need to:
Open Advanced Mode in the Groupings pane. (Click the arrow to the right of the Column Groups and select Advanced Mode.)
In the Row Gr...