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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
...
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 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]
...
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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Add a prefix string to beginning of each line
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PhysicalChemist
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answered Jan 20 '10 at 6:38
Alok SinghalAlok Singhal
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How to remove text from a string?
... |
edited Feb 28 at 9:20
Community♦
111 silver badge
answered May 1 '12 at 14:14
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Are std::vector elements guaranteed to be contiguous?
... C++98 standard proper but later added as part of a TR. The forthcoming C++0x standard will of course contain this as a requirement.
From n2798 (draft of C++0x):
23.2.6 Class template vector [vector]
1 A vector is a sequence container that supports random access iterators. In addition, it ...