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Transposing a 2D-array in JavaScript
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array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided callback function once for each element in an array, in order, and constructs a new array from the results. callback is invoked only for indexe...
How should I edit an Entity Framework connection string?
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I had to explicitly call save on the app.config file for the designer to recognise the connection string had been deleted.
– Rossco
May 9 '14 at 2:37
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How can I determine whether a 2D Point is within a Polygon?
...integers. Many systems use integers for UI painting (pixels are ints after all), but macOS for example uses float for everything. macOS only knows points and a point can translate to one pixel, but depending on monitor resolution, it might translate to something else. On retina screens half a point ...
How does the bitwise complement operator (~ tilde) work?
...ng the binary representation of a number, taking its complement (inverting all the bits) and adding one. Two starts as 0000 0010, and by inverting the bits we get 1111 1101. Adding one gets us the result above. The first bit is the sign bit, implying a negative.
So let's take a look at how we get ~2...
What is the meaning of “$” sign in JavaScript
...of $ in JavaScript. $ is simply a valid JavaScript identifier.
JavaScript allows upper and lower letters, numbers, and $ and _. The $ was intended to be used for machine-generated variables (such as $0001).
Prototype, jQuery, and most javascript libraries use the $ as the primary base object (or f...
OnCreateOptionsMenu() not called in Fragment
I have an app which got one activity with 2 fragments placed horizontally.
8 Answers
8...
Escaping HTML strings with jQuery
... jsbin.com/fazimigayo/1/edit?html,js,console,output (and it should work on all earlier versions too)
– Henrik N
Nov 5 '16 at 20:46
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Can I force a page break in HTML printing?
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Add a CSS class called "pagebreak" (or "pb"), like so:
@media print {
.pagebreak { page-break-before: always; } /* page-break-after works, as well */
}
Then add an empty DIV tag (or any block element that generates a box) where you wan...
How to save a PNG image server-side, from a base64 data string
...plode(';', $data);
list(, $data) = explode(',', $data);
$data = base64_decode($data);
file_put_contents('/tmp/image.png', $data);
And as a one-liner:
$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));
An efficient method for extracting, decoding, and checking for e...
Renaming columns in pandas
...UMNS
Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:
df = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})
# Or rename the existing DataFrame (rather than creating a copy)
df.rename(columns={'oldName1': 'newName1', 'oldNam...