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What does it mean if a Python object is “subscriptable” or not?
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The [...] indexing syntax is called a subscript, because it's equivalent to mathematical notation that uses actual subscripts; e.g. a[1] is Python for what mathematicians would write as a₁. So "subscriptable" means "able to be subscr...
Should I use a data.frame or a matrix?
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Part of the answer is contained already in your question: You use data frames if columns (variables) can be expected to be of different types (numeric/character/logical etc.). Matrices are for data of the same type.
Consequently, the choice matrix/data.frame is only prob...
What's the “average” requests per second for a production web application?
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@JosephPersie Don't forget to look at the post date, hehe.
– Spectral
Oct 14 '19 at 23:56
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Store print_r result into a variable as a string or text
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Find object by id in an array of JavaScript objects
...ing function. Otherwise undefined is returned.
If you want to find its index instead, use findIndex():
myArray.findIndex(x => x.id === '45');
From MDN:
The findIndex() method returns the index of the first element in the array that satisfies the provided testing function. Otherwise -1 ...
How does one reorder columns in a data frame?
...order by column name
data <- data[c("A", "B", "C")]
#reorder by column index
data <- data[c(1,3,2)]
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How can I unstage my files again after making a local commit?
... should do what you want. After this, you'll have the first changes in the index (visible with git diff --cached), and your newest changes not staged. git status will then look like this:
# On branch master
# Changes to be committed:
# (use "git reset HEAD <file>..." to unstage)
#
# m...
Tetris-ing an array
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$common = PHP_INT_MAX;
foreach ($a as $item) {
$common = min($common, str_common($a[0], $item, $common));
}
$result = array();
foreach ($a as $item) {
$result[] = substr($item, $common);
}
print_r($result);
function s...
AJAX post error : Refused to set unsafe header “Connection”
I have the following custom ajax function that posts data back to a PHP file. Everytime the post of data happens I get the following two errors :
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How to style the parent element when hovering a child element?
... background: blue;
border-radius: 10px;
position: relative;
z-index: 1;
}
.item span.icon-cross:hover::after {
background: DodgerBlue;
border-radius: 10px;
display: block;
position: absolute;
z-index: -1;
top: 0;
left: 0;
right: 0;
bottom: 0;
cont...