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Is arr.__len__() the preferred way to get the length of an array in Python?
...5
The same works for tuples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
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And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
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It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to expl...
how to use sed, awk, or gawk to print only what is matched?
I see lots of examples and man pages on how to do things like search-and-replace using sed, awk, or gawk.
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Select unique or distinct values from a list in UNIX shell script
I have a ksh script that returns a long list of values, newline separated, and I want to see only the unique/distinct values. It is possible to do this?
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Is there a standard sign function (signum, sgn) in C/C++?
I want a function that returns -1 for negative numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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What is mutex and semaphore in Java ? What is the main difference?
What is mutex and semaphore in Java ? What is the main difference ?
11 Answers
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How to use Java property files?
...alue pairs of configuration values I want to store as Java property files, and later load and iterate through.
17 Answers
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Does a javascript if statement with multiple conditions test all of them?
...IT: Though, you shouldn't worry about performance until you've benchmarked and determined that it's a problem. Premature micro-optimization is the bane of maintainability.
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Counting the number of elements with the values of x in a vector
... x creates a logical vector which is TRUE at every location that x occurs, and when suming, the logical vector is coerced to numeric which converts TRUE to 1 and FALSE to 0.
However, note that for floating point numbers it's better to use something like: sum(abs(numbers - x) < 1e-6).
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Is it possible only to declare a variable without assigning any value in Python?
...es. If you init something to None, make sure that's what you really want, and assign something more meaningful if you can.
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How to convert DateTime to VarChar
...ing from character data to datetime or smalldatetime". See the footnotes 6 and 7 at docs.microsoft.com/de-de/sql/t-sql/functions/…
– Colin
Sep 4 '17 at 11:15
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