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Count character occurrences in a string in C++
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Small note, but the return type is typically signed. For some reason std::count returns type iterator_traits<InputIt>::difference_type, which for most standard containers is std::ptrdiff_t, not std::size_t.
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One-liner to check whether an iterator yields at least one element?
... Similarly if you need to check if the iterator is empty, one could use all(False for _ in iterator) will check if the iterator is empty. (all returns True if the iterator is empty, otherwise it stops when it sees the first False element)
– KGardevoir
Apr 3 ...
What is the difference between join and merge in Pandas?
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pandas.merge() is the underlying function used for all merge/join behavior.
DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...
Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
...at I'll refer to as "the Gmail three-fragment animation" scenario. Specifically, we want to start with two fragments, like this:
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Calling class staticmethod within the class body?
... def stat_func():
return 42
_ANS = stat_func.__func__() # call the staticmethod
def method(self):
ret = Klass.stat_func()
return ret
As an aside, though I suspected that a staticmethod object had some sort of attribute storing the original function, I had no ...
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
... gcc-4.8 1.53s 1.52s -Os
In some cases you can alleviate the effect of disadvantageous optimizations by asking gcc to optimize for your particular processor (using options -mtune=native or -march=native):
Processor Compiler Time (-O2 -mtune=native) Time (-Os...
How can I add reflection to a C++ application?
...rate the data about each field(plus the field itself). This macro will be called like this:
REFLECTABLE
(
(const char *) name,
(int) age
)
So using Boost.PP we iterate over each argument and generate the data like this:
// A helper metafunction for adding const to a type
template<clas...
How do I clear only a few specific objects from the workspace?
I would like to remove some data from the workspace. I know the "Clear All" button will remove all data. However, I would like to remove just certain data.
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Code Golf: Lasers
...is sitting on top of now. Since the laser emitter is to be treated like a wall, set this to be a wall to begin with.
if (tr/v<^/>v</) {
my $o;
$o .= "\n" while s/.$/$o .= $&, ""/meg;
tr,/\\,\\/, for $o, $s;
$_ = $o;
}
If the laser beam is pointing any way except right, rotate...
How to use the pass statement?
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I really don't think this properly answers the question. Citing one possible use for something, even if it is the most common use for it, is not the same as explaining what it is for.
– Schilcote
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