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Sort array of objects by single key with date value
...cts with several key value pairs, and I need to sort them based on 'updated_at':
19 Answers
...
How does Google's Page Speed lossless image compression work?
...lly interested in the technical details, check out the source code:
png_optimizer.cc
jpeg_optimizer.cc
webp_optimizer.cc
For PNG files, they use OptiPNG with some trial-and-error approach
// we use these four combinations because different images seem to benefit from
// different parameters...
CSS hexadecimal RGBA?
...vtools on Chrome 55. No dice, it errors as an invalid property value... ¯\_(ツ)_/¯
– ericsoco
Jan 18 '17 at 21:04
...
Is there a way to iterate over a dictionary?
...alue] = value;
}
... summing up the numbers with the block approach ...
__block int sum = 0;
[dict enumerateKeysAndObjectsUsingBlock:^(NSString* key, NSNumber* value, BOOL* stop) {
sum += value.intValue;
}];
... rather than the loop approach ...
int sum = 0;
for (NSString* key in dict)
sum...
Get time difference between two dates in seconds
...
<script type="text/javascript">
var _initial = '2015-05-21T10:17:28.593Z';
var fromTime = new Date(_initial);
var toTime = new Date();
var differenceTravel = toTime.getTime() - fromTime.getTime();
var seconds = Math.floor((differenceTravel) / (1000));
document...
binning data in python with scipy/numpy
...
bins = numpy.linspace(0, 1, 10)
digitized = numpy.digitize(data, bins)
bin_means = [data[digitized == i].mean() for i in range(1, len(bins))]
An alternative to this is to use numpy.histogram():
bin_means = (numpy.histogram(data, bins, weights=data)[0] /
numpy.histogram(data, bins)[0...
Signed to unsigned conversion in C - is it always safe?
...hort Answer
Your i will be converted to an unsigned integer by adding UINT_MAX + 1, then the addition will be carried out with the unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions...
Get file size, image width and height before upload
...;img src="blob:null/026cceb9-edr4-4281-babb-b56cbf759a3d">
const EL_browse = document.getElementById('browse');
const EL_preview = document.getElementById('preview');
const readImage = file => {
if ( !(/^image\/(png|jpe?g|gif)$/).test(file.type) )
return EL_preview.insertAdj...
How to check if command line tools is installed
...o $?
10.9 Mavericks Update:
Use pkgutil --pkg-info=com.apple.pkg.CLTools_Executables
10.8 Update:
Option 1: Rob Napier suggested to use pkgutil --pkg-info=com.apple.pkg.DeveloperToolsCLI, which is probably cleaner.
Option 2: Check inside /var/db/receipts/com.apple.pkg.DeveloperToolsCLI.plist f...
Is there a JavaScript / jQuery DOM change listener?
...e kind of fingerprinting the existing contents.
Cloaking History API:
let _pushState = History.prototype.pushState;
History.prototype.pushState = function (state, title, url) {
_pushState.call(this, state, title, url);
console.log('URL changed', url)
};
Listening to hashchange, popstate event...