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What is the best way to determine the number of days in a month with JavaScript?
...
Unfortunately this fails for dates before 1000 AD where you can only set the year correctly by using SetFullYear(). To make it bullet proof use new Date( 2000+(year%2000), month, 0 ).getDate()
– Noel Walters
Feb 20 '13 at 14:55
...
What is the “-->” operator in C++?
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+100
It's equivalent to
while (x-- > 0)
x-- (post decrement) is equivalent to x = x-1 so, the code transforms to:
while(x > 0) ...
Modifying a subset of rows in a pandas dataframe
...ease, use NumPy's where function.
Setup
Create a two-column DataFrame with 100,000 rows with some zeros.
df = pd.DataFrame(np.random.randint(0,3, (100000,2)), columns=list('ab'))
Fast solution with numpy.where
df['b'] = np.where(df.a.values == 0, np.nan, df.b.values)
Timings
%timeit df['b'] = np.w...
How can I output leading zeros in Ruby?
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filenames = '000'.upto('100').map { |index| "file_#{index}" }
Outputs
[file_000, file_001, file_002, file_003, ..., file_098, file_099, file_100]
share
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How can I read command line parameters from an R script?
...ogram Files\R-3.0.2\bin\RScript.exe"
%R_Script% exmpl.R 2010-01-28 example 100 > exmpl.batch 2>&1
Alternatively, using Rterm.exe:
set R_TERM="C:\Program Files\R-3.0.2\bin\i386\Rterm.exe"
%R_TERM% --no-restore --no-save --args 2010-01-28 example 100 < exmpl.R > exmpl.batch 2>&am...
Is there a `pointer-events:hoverOnly` or similar in CSS?
...;
height: 300px;
}
#overlay {
background-color: black;
width: 100%;
height: 100%;
opacity: 0;
z-index: 1;
/* Pass through clicks */
pointer-events: none;
}
/*
Set overlay hover style based on
:hover pseudo-element of its
container
*/
#container:hove...
How can I get every nth item from a List?
...ne in a linq friendly manner then you could lazily eval and take the first 100 value eg `` source.TakeEvery(5).Take(100) `` If the underlying source was expensive to eval then your approach would cause every element to be evaluated
– RhysC
Dec 11 '15 at 6:4...
possible EventEmitter memory leak detected
...Listeners via:
const emitter = new EventEmitter()
emitter.setMaxListeners(100)
// or 0 to turn off the limit
emitter.setMaxListeners(0)
But if it's not your code you can use the trick to increase the default limit globally:
require('events').EventEmitter.prototype._maxListeners = 100;
Of cours...
STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
... int m_a;
};
...
map<a, int> mp;
a a1;
a1.m_a = 100;
a1.pName = "a1";
a a2;
a2.m_a = 200;
a2.pName = "a2";
mp.insert(std::make_pair(a1, 1));
mp.insert(std::make_pair(a2, 1));
编译出错
初始化结构体对象，添加到容器...
CSS: fixed position on x-axis but not y?
...ition-fixed-y').css('top', $w.scrollTop());
});
.container {
width: 1000px;
}
.position-fixed-x {
position: relative;
}
.position-fixed-y {
position: relative;
}
.blue-box {
background:blue;
width: 50px;
height: 50px;
}
.red-box {
background: red;
width: ...