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What C++ Smart Pointer Implementations are available?
...
C++03
std::auto_ptr - Perhaps one of the originals it suffered from first draft syndrome only providing limited garbage collection facilities. The first downside being that it calls delete upon destruction making them unaccepta...
Javascript reduce() on Object
...}
}
const total = Object.values(add).reduce((t, {value}) => t + value, 0)
console.log(total) // 6
or simply:
const add = {
a: 1,
b: 2,
c: 3
}
const total = Object.values(add).reduce((t, n) => t + n)
console.log(total) // 6
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Diff Algorithm? [closed]
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answered Aug 21 '09 at 17:23
jscharfjscharf
5,27022 gold badges1919 silver badges1515 bronze badges
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count the frequency that a value occurs in a dataframe column
...['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2
3 s 2
4 b 3
5 a 2
6 b 3
[7 rows x 2 columns]
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How can I efficiently select a Standard Library container in C++11?
...edited May 16 '16 at 7:29
user2508324
answered May 22 '12 at 11:26
Matthieu M.Matthieu M.
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What's the best way to iterate over two or more containers simultaneously
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10 Answers
10
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How can I extract embedded fonts from a PDF as valid font files?
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406
You have several options. All these methods work on Linux as well as on Windows or Mac OS X. Ho...
Wrap long lines in Python [duplicate]
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def fun():
print(('{0} Here is a really long '
'sentence with {1}').format(3, 5))
Adjacent string literals are concatenated at compile time, just as in C. http://docs.python.org/reference/lexical_analysis.html#string-literal-concate...
Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...l evaluate to true if value is not:
null
undefined
NaN
empty string ("")
0
false
The above list represents all possible falsy values in ECMA-/Javascript. Find it in the specification at the ToBoolean section.
Furthermore, if you do not know whether a variable exists (that means, if it was decla...
Unique random string generation
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answered Apr 8 '09 at 14:58
Mark SynowiecMark Synowiec
4,9371919 silver badges1818 bronze badges
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