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Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
7
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Is there an exponent operator in C#?
...o in most programs, and
it doesn't seem justified to add an
operator when calling Math.Pow() is
simple.
You asked:
Do I have to write a loop or include
another namespace to handle
exponential operations? If so, how do
I handle exponential operations using
non-integers?
Math.Pow supports double p...
Is it possible in SASS to inherit from a class in another file?
The question pretty much says it all.
4 Answers
4
...
How do I activate a virtualenv inside PyCharm's terminal?
...with multiple projects, each which might have a different virtualenv, I'd call the ".pycharmrc" file something different, and perhaps put it into the env directory itself. ~/pycharmenv/bin/terminalactivate sounds like a good option.
– Chris Cogdon
Mar 10 '14 at...
Why no generics in Go?
... id types. Type information is preserved and can be "cast" (asserted, actually) back to its concrete type. Get the gritty details here: golang.org/ref/spec#Type_assertions
– tbone
Aug 25 '13 at 20:50
...
Create folder with batch but only if it doesn't already exist
... @jpmc26 You are right, a trailing slash does the job and is actually preferable since it works with quotes (thus allowing you to have spaces in the directory path). To distinguish between either file/directory, this will work: if exist "a" if not exist "a\" (echo "it's a file") else (echo...
When should you not use virtual destructors?
...o not declare a virtual destructor for a class? When should you specifically avoid writing one?
12 Answers
...
Time complexity of Sieve of Eratosthenes algorithm
...oose upper-bound is n(1+1/2+1/3+1/4+1/5+1/6+…1/n) (sum of reciprocals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound is n(1/2 + 1/3 + 1/5 + 1/7 + …), that is sum of reciprocals of primes up to n, which is O(n log log n). (See here or here.)
The "find...
Is there an alternative sleep function in C to milliseconds?
...s defined usleep(), so this is available on Linux:
int usleep(useconds_t usec);
DESCRIPTION
The usleep() function suspends execution of the calling thread for
(at least) usec microseconds. The sleep may be lengthened slightly by
any system activity or by the tim...
Is git not case sensitive?
In the first commitment of my partial called _Electronics it was written beginning with a capital letters, then I changed it to _electronics .
...