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Deleting DataFrame row in Pandas based on column value
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Good update for query. It allows for more rich selection criteria (eg. set-like operations like df.query('variable in var_list') where 'var_list' is a list of desired values)
– philE
Sep 30 '14 at 20:32
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How to define an enumerated type (enum) in C?
...ollowing works without any complaints (compiled with gcc -ansi -pedantic -Wall):
#include <stdio.h>
enum { RANDOM, IMMEDIATE, SEARCH } strategy = IMMEDIATE;
int main(int argc, char** argv){
printf("strategy: %d\n", strategy);
return 0;
}
If instead of the above, the second line wer...
Creating temporary files in Android
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This is what I typically do:
File outputDir = context.getCacheDir(); // context being the Activity pointer
File outputFile = File.createTempFile("prefix", "extension", outputDir);
As for their deletion, I am not complete sure either. Since I ...
Volley Android Networking Library
... I had to go to 5 different google results to find the instructions to install their own networking library.
– Gowiem
Aug 28 '13 at 18:19
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What's the use/meaning of the @ character in variable names in C#?
...terfacing with other
programming languages. The character @
is not actually part of the
identifier, so the identifier might be
seen in other languages as a normal
identifier, without the prefix. An
identifier with an @ prefix is called
a verbatim identifier.
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Python SQL query string formatting
...l query string. When I'm debugging
my application I'd like to log to file all the sql query strings, and it is
important that the string is properly formated.
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Are Javascript arrays sparse?
...ript arrays are implemented differs from browser to browser, but they generally fall back to a sparse implementation - most likely the same one used for property access of regular objects - if using an actual array would be inefficient.
You'll have to ask someone with more knowledge about specific ...
Class constants in python
In python, I want a class to have some "constants" (practically, variables) which will be common in all subclasses. Is there a way to do it with friendly syntax?
Right now I use:
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Which is the fastest algorithm to find prime numbers?
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Actually I don't think primegen is the fastest, or even the second-fastest; yafu and primesieve are both faster in general, I think, and certainly over 2^32. Both are (modified) sieves of Eratosthenes rather than the Atkin-Berns...
Why use static_cast(x) instead of (int)x?
...e main reason is that classic C casts make no distinction between what we call static_cast<>(), reinterpret_cast<>(), const_cast<>(), and dynamic_cast<>(). These four things are completely different.
A static_cast<>() is usually safe. There is a valid conversion in the...