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What is an intuitive explanation of the Expectation Maximization technique? [closed]
...e could find the exact means if we wanted).
This is, generally speaking, known as maximum likelihood estimation. Given some data, we compute the value of a parameter (or parameters) that best explains that data.
Now imagine that we cannot see which value was sampled from which group. Everything lo...
Using the Swift if let with logical AND operator &&
We know that we can use an if let statement as a shorthand to check for an optional nil then unwrap.
6 Answers
...
Mercurial move changes to a new branch
...eans, revision 0 is the base on which you started to work on your feature. Now you want to have revisions 1-2 on a named branch, let's say my-feature. Update to revision 0 and create that branch:
$ hg up 0
$ hg branch my-feature
$ hg ci -m "start new branch my-feature"
The history now looks like ...
How do I configure Notepad++ to use spaces instead of tabs?
...
Ah Language, now that makes sense.
– deed02392
Dec 5 '13 at 16:05
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JavaScript and Threads
...ript Worker Threads
Apart from from Gears there's nothing available right now, but there's plenty of talk about how to implement this so I guess watch this question as the answer will no doubt change in future.
Here's the relevant documentation for Gears: WorkerPool API
WHATWG has a Draft Recomme...
Converting timestamp to time ago in PHP e.g 1 day ago, 2 days ago…
...
Function :
function time_elapsed_string($datetime, $full = false) {
$now = new DateTime;
$ago = new DateTime($datetime);
$diff = $now->diff($ago);
$diff->w = floor($diff->d / 7);
$diff->d -= $diff->w * 7;
$string = array(
'y' => 'year',
'...
How to run Selenium WebDriver test cases in Chrome?
...
Now that's a cumbersome solution. I'd advise you to change this if it's what you use nowadays.
– aimbire
Mar 21 '13 at 17:19
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Null coalescing in powershell
... evaluated
Null Conditional Assignment
$x = $null
$x ??= 100 # $x is now 100
$x ??= 200 # $x remains 100
Ternary Operator
$true ? "this value returned" : "this expression not evaluated"
$false ? "this expression not evaluated" : "this value returned"
Previous Versions:
No need for ...
Generating a drop down list of timezones with PHP
...eported a bug for the same error as Xeoncross and was wondering if anyone knows how this is possible? The manual seems to indicate that these constants are available since PHP5.2 but is this incorrect?
– brendo
Apr 8 '11 at 1:20
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arrayfun can be significantly slower than an explicit loop in matlab. Why?
...n2 10.392475 seconds.
Soln3 0.239023 seconds.
Oli 0.010672 seconds.
Now, while the fully 'vectorized' solution is clearly the fastest, you can see that defining a function to be called for every x entry is a huge overhead. Just explicitly writing out the computation got us factor 5 speedup. I...