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How to sort with a lambda?
...nclude <iostream>
#include <sstream>
struct Foo
{
Foo() : _i(0) {};
int _i;
friend std::ostream& operator<<(std::ostream& os, const Foo& f)
{
os << f._i;
return os;
};
};
typedef std::vector<Foo> VectorT;
std::string ...
Convert Python dictionary to JSON array
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If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
Is there a way to tell git to only include certain files instead of ignoring certain files?
My programs generally generate huge output files (~1 GB) which I do not want to be backing up to the git repository. So instead of being able to do
...
Why declare a struct that only contains an array in C?
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It allows you to pass the array to a function by value, or get it returned by value from a function.
Structs can be passed by value, unlike arrays which decay to a pointer in these contexts.
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Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewe...
Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
What is the difference between .text, .value, and .value2?
...presenting what is displayed on the screen for the cell. Using .Text is usually a bad idea because you could get ####
.Value2 gives you the underlying value of the cell (could be empty, string, error, number (double) or boolean)
.Value gives you the same as .Value2 except if the cell was formatted...
onCreateOptionsMenu inside Fragments
...nsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_sample, menu);
super.onCreateOptionsMenu(menu,inflater);
}
And in onCreate add this line to make the options appear in your Toolbar
setHasOptionsMenu(true);
...
How to compare type of an object in Python?
Basically I want to do this:
14 Answers
14
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Get the value of an instance variable given its name
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The most idiomatic way to achieve this is:
some_object.instance_variable_get("@#{name}")
There is no need to use + or intern; Ruby will handle this just fine. However, if you find yourself reaching into another object and pulling out its ivar, there's a reasonably good ...