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Integer division: How do you produce a double?
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I don't like casting primitives, who knows what may happen.
Why do you have an irrational fear of casting primitives? Nothing bad will happen when you cast an int to a double. If you're just not sure of how it works, look it up in the Java Language Specificatio...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...is will throw a NullReferenceException in the second line and you want to know why .NET doesn't tell you that it was s that was null when the exception was thrown.
To understand why you don't get that piece of information you should remember that it is not C# source that executes but rather IL:
I...
What are the use-cases for Web Workers? [closed]
... changing, wait till status changes to "all calculations complete, you can now review the final #s and save".
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Convert one date format into another in PHP
...e current date (or datetime) in a specific format then it's even easier:
$now = new DateTime();
$timestring = $now->format('Y-m-d h:i:s');
This other question also refers to the same topic: Convert date format yyyy-mm-dd => dd-mm-yyyy.
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Statistics: combinations in Python
... N and K due to floating point precision. But we can fix that - see above, now it should not err for big numbers
– Nas Banov
Sep 17 '13 at 1:17
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Javascript Cookie with no expiration date
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It's edited to 2030 now, we're postponing our doom 10 more years
– Simeon Nakov
Feb 23 '18 at 11:47
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Repairing Postgresql after upgrading to OSX 10.7 Lion
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It's a PATH issue. Mac OSX Lion includes Postgresql in the system now. If you do a which psql you'll likely see usr/bin/psql instead of usr/local/bin/psql which is HomeBrew's correct one. If you run brew doctor you should get a message stating that you need to add usr/local/bin to the head ...
use localStorage across subdomains
...afari 7+ both on desktop and mobile to block 3rd party data. The option is now called "Block cookies and other website data" which refers to things like localstorage which are now completely isolated by domain. This method wont work in Safari
– Aranganathan
Jul...
Insert new item in array on any position in PHP
...( $original, 3, 0, $inserted ); // splice in at position 3
// $original is now a b c x d e
If replacement is just one element it is not necessary to put array() around it, unless the element is an array itself, an object or NULL.
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How to remove convexity defects in a Sudoku square?
...a mask for the sudoku grid:
mask = FillingTransform[largestComponent]
Now, I can use a 2nd order derivative filter to find the vertical and horizontal lines in two separate images:
lY = ImageMultiply[MorphologicalBinarize[GaussianFilter[srcAdjusted, 3, {2, 0}], {0.02, 0.05}], mask];
lX = Image...