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How to initialize an array's length in JavaScript?
...(function () {}) gives you an array with length 5 and undefined as values, now it can be iterated over.
Array.apply(null, Array(5)).map(function (x, i) { return i; }) gives you an array with length 5 and values 0,1,2,3,4.
Array(5).forEach(alert) does nothing, Array.apply(null, Array(5)).forEach(aler...
Converting strings to floats in a DataFrame
...
NOTE: pd.convert_objects has now been deprecated. You should use pd.Series.astype(float) or pd.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will fail; its als...
difference between variables inside and outside of __init__()
...e I could access both kind of variables through the self reference. It was now, when I ran into trouble, that I researched the topic and cleared it up.
The problem with accessing static class variables through the
self reference is that it only references the static class variable if there is no i...
What is a good pattern for using a Global Mutex in C#?
...owEveryoneRule =
new MutexAccessRule( new SecurityIdentifier( WellKnownSidType.WorldSid
, null)
, MutexRights.FullControl
, AccessControlType.Allow
);
var s...
What is a loop invariant?
...be no number such that start <= mid and mid <= end and therefore we know that the statement A[mid] == a must be false. However, as a result the overall logical statement is still true in the null sense. ( In logic the statement if ( false ) then ( something ) is always true. )
Now what abou...
What happens to C# Dictionary lookup if the key does not exist?
...corresponding value
}
else
{
// Key wasn't in dictionary; "value" is now 0
}
(Using ContainsKey and then the the indexer makes it look the key up twice, which is pretty pointless.)
Note that even if you were using reference types, checking for null wouldn't work - the indexer for Dictionary...
How to find day of week in php in a specific timezone
... Europe/Stockholm to the users time-zone.
$dateTime = new \DateTime(
'now',
new \DateTimeZone('Europe/Stockholm')
);
$day = $dateTime->format('N');
ISO-8601 numeric representation of the day of the week (added in PHP 5.1.0)
1 (for Monday) through 7 (for Sunday)
http://php.net/ma...
How to access full source of old commit in BitBucket?
...g/user/project/commits/0000000000000000000000000000000000000000?at=master. Now, just change commits in the url to src and you are browsing the full source at this commit!
– Peter
Sep 15 '17 at 14:07
...
Create a string of variable length, filled with a repeated character
... new repeat function built into String.prototype handles this now (ES6+)
– AlexMA
Oct 18 '16 at 18:05
...
You have already activated X, but your Gemfile requires Y
...is.
Basically what's happening is that you've updated rake to 0.9.2 which now conflicts with the version specified in your Gemfile. Previously the latest version of rake you had matched the version in your Gemfile, so you didn't get any warning when simply using rake.
Yehuda Katz (one of the origi...