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Does the ternary operator exist in R?
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306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a...
How to declare constant map
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edited Feb 23 '17 at 22:50
Robert P
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PHP Pass by reference in foreach [duplicate]
...ee');
foreach ($a as &$v) {
}
foreach ($a as $v) {
echo $v.'-'.$a[3].PHP_EOL;
}
As you can see, the last array item takes the current loop value: 'zero', 'one', 'two', and then it's just 'two'... : )
share
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What's the magic of “-” (a dash) in command-line parameters?
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edited Nov 8 '11 at 3:15
answered Nov 8 '11 at 3:09
p...
Python - When to use file vs open
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153
You should always use open().
As the documentation states:
When opening a file, it's prefer...
RegEx - Match Numbers of Variable Length
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135
{[0-9]+:[0-9]+}
try adding plus(es)
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How to convert list of key-value tuples into dictionary?
...injagecko
72.5k2121 gold badges124124 silver badges134134 bronze badges
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Using async/await for multiple tasks
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int[] ids = new[] { 1, 2, 3, 4, 5 };
Parallel.ForEach(ids, i => DoSomething(1, i, blogClient).Wait());
Although you run the operations in parallel with the above code, this code blocks each thread that each operation runs on. For example, if the ...
Efficient way to apply multiple filters to pandas DataFrame or Series
...'col1'] >= 1]
Out[12]:
col1 col2
1 1 11
2 2 12
In [13]: df[(df['col1'] >= 1) & (df['col1'] <=1 )]
Out[13]:
col1 col2
1 1 11
If you want to write helper functions for this, consider something along these lines:
In [14]: def b(x, col, op, n):
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