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SQL - using alias in Group By
...ceptions though: MySQL and Postgres seem to have additional smartness that allows it.
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Listen for key press in .NET console app
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Use Console.KeyAvailable so that you only call ReadKey when you know it won't block:
Console.WriteLine("Press ESC to stop");
do {
while (! Console.KeyAvailable) {
// Do something
}
} while (Console.ReadKey(true).Key != ConsoleKey.Escape);
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Apply multiple functions to multiple groupby columns
...ion.
I recommend making a single custom function that returns a Series of all the aggregations. Use the Series index as labels for the new columns:
def f(x):
d = {}
d['a_sum'] = x['a'].sum()
d['a_max'] = x['a'].max()
d['b_mean'] = x['b'].mean()
d['c_d_prodsum'] = (x['c'] * x['d...
Timeout function if it takes too long to finish [duplicate]
...nal
class TimeoutError(Exception):
pass
def timeout(seconds=10, error_message=os.strerror(errno.ETIME)):
def decorator(func):
def _handle_timeout(signum, frame):
raise TimeoutError(error_message)
def wrapper(*args, **kwargs):
signal.signal(signal.SI...
Python: changing value in a tuple
...'m new to python so this question might be a little basic. I have a tuple called values which contains the following:
17 ...
AngularJS. How to call controller function from outside of controller component
How I can call function defined under controller from any place of web page (outside of controller component)?
10 Answers
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Program only crashes as release build — how to debug?
I've got a "Schroedinger's Cat" type of problem here -- my program (actually the test suite for my program, but a program nonetheless) is crashing, but only when built in release mode, and only when launched from the command line. Through caveman debugging (ie, nasty printf() messages all over the ...
How do I enable EF migrations for multiple contexts to separate databases?
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The 2nd call to Enable-Migrations is failing because the Configuration.cs file already exists. If you rename that class and file, you should be able to run that 2nd Enable-Migrations, which will create another Configuration.cs.
You ...
Passing base64 encoded strings in URL
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en.wikipedia.org/wiki/Base64#URL_applications — it says clearly that escaping ‘makes the string unnecessarily longer’ and mentions the alternate charset variant.
– Michał Górny
Sep 3 '09 at 23:02
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Difference between std::result_of and decltype
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result_of was introduced in Boost, and then included in TR1, and finally in C++0x. Therefore result_of has an advantage that is backward-compatible (with a suitable library).
decltype is an entirely new thing in C++0x, does not restrict only to return type of a function, and is a language fe...