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Is there a range class in C++11 for use with range based for loops?
I found myself writing this just a bit ago:
8 Answers
8
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Deleting an element from an array in PHP
...d keys starting from 0.
Code
<?php
$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
//↑ Key which you want to delete
?>
Output
[
[0] => a
[2] => c
]
\array_splice() method
If you use \array_splice() the keys will be automatically r...
Using relative URL in CSS file, what location is it relative to?
When defining something like a background image URL in a CSS file, when using a relative URL, where is it relative to? For example:
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How to move one word left in the vi editor
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Use b to move back one word.
Use w to move forward one word.
And here is a cheat sheet that might be useful for you:
Source: Graphical vi-vim Cheat Sheet and Tutorial
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Compare if two variables reference the same object in python
How to check whether two variables reference the same object?
6 Answers
6
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Dynamic instantiation from string name of a class in dynamically imported module?
In python, I have to instantiate certain class, knowing its name in a string, but this class 'lives' in a dynamically imported module. An example follows:
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...nt of a vector or data frame is a duplicate of an element with a smaller subscript. So if rows 3, 4, and 5 of a 5-row data frame are the same, duplicated will give me the vector
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
Let's say I have the following data.table in R :
3 Answers
3
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