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What is the most efficient way to loop through dataframes with pandas? [duplicate]
...Note that iterrows is very slow (it converts every row to a series, potentially messing with your data types). When you need an iterator, better to use itertuples
– joris
Jul 29 '15 at 15:46
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JavaScript: location.href to open in new window/tab?
...notification in modern browsers, doesn't simulate a _blank anchor click at all.
– Nathan Hornby
Oct 1 '14 at 12:46
22
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Why switch is faster than if
...uct Packet
{
void(*execute)() = NULL;
};
Packet incoming_packet[255];
uint8_t test_value = 0;
void A()
{
std::cout << "I'm the 1st test.\n";
}
void B()
{
std::cout << "I'm the 2nd test.\n";
}
void Empty()
{
}
void Update()
{
if (incoming_packet[test_value].exe...
How can I remove non-ASCII characters but leave periods and spaces using Python?
...
You can filter all characters from the string that are not printable using string.printable, like this:
>>> s = "some\x00string. with\x15 funny characters"
>>> import string
>>> printable = set(string.printable)
...
getting type T from IEnumerable
... Or even worse write a method with yield returns and try to call GetType on a variable created with this method. It will tell you that it is not event a generic type. So basically there is no universal way to get T given an instance variable of type IEnumerable<T>
...
Serializing class instance to JSON
...ps() only knows how to serialize a limited set of object types by default, all built-in types. List here: https://docs.python.org/3.3/library/json.html#encoders-and-decoders
One good solution would be to make your class inherit from JSONEncoder and then implement the JSONEncoder.default() function...
Is it better in C++ to pass by value or pass by constant reference?
...
It used to be generally recommended best practice1 to use pass by const ref for all types, except for builtin types (char, int, double, etc.), for iterators and for function objects (lambdas, classes deriving from std::*_function).
This was es...
What is the difference between a static and a non-static initialization code block
...own, just like simple variable initializers) when the class is loaded (actually, when it's resolved, but that's a technicality).
Instance initializers are executed in the order defined when the class is instantiated, immediately before the constructor code is executed, immediately after the invocat...
Variable number of arguments in C++?
...u can probably do what you want to do in a safer and simpler way. Technically to use variable number of arguments in C you include stdarg.h. From that you'll get the va_list type as well as three functions that operate on it called va_start(), va_arg() and va_end().
#include<stdarg.h>
int...
Using multiple delimiters in awk
... fedorqui 'SO stop harming'
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answered Aug 30 '12 at 19:47
embedded.kyleembedded.kyle
...