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Append column to pandas dataframe
...lid with uniquely valued Index objects , you can use: pd.concat([dat1.reset_index(), dat2], axis=1)
– beyondfloatingpoint
Aug 27 '19 at 9:21
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Get time difference between two dates in seconds
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<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...
How to present popover properly in iOS 8
... you talk to the view controller inside of it to set the content size, by calling the property preferredContentSize
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How to sort a Ruby Hash by number value?
...ea.com" => 745, "siteb.com" => 9, "sitec.com" => 10 }
metrics.sort_by {|_key, value| value}
# ==> [["siteb.com", 9], ["sitec.com", 10], ["sitea.com", 745]]
If you need a hash as a result, you can use to_h (in Ruby 2.0+)
metrics.sort_by {|_key, value| value}.to_h
# ==> {"siteb.c...
Why should I declare a virtual destructor for an abstract class in C++?
...structor when deleting a pointer to a base class.
– j_random_hacker
Feb 10 '09 at 10:10
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How do I instantiate a Queue object in java?
...n't want to do this, but it's listed as an option for the sake of covering all the bases.
new Queue<Tree>() {
public Tree element() {
...
};
public boolean offer(Tree element) {
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};
...
};
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Safe (bounds-checked) array lookup in Swift, through optional bindings?
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WARNING! Checking arrays this way can be really expensive. The contains method will iterate through all indices thus making this an O(n). A better way is to use the index and count to check the bounds.
– Stefan Vasiljevic
May 7 '...
How do I read an attribute on a class at runtime?
...d be further generalized by extending MemberInfo, a base class of Type and all - or at least most - of a Type's members. Doing so would open this up to allow reading attributes from Properties, Fields, and even Events.
– M.Babcock
Aug 12 '14 at 1:54
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PSQLException: current transaction is aborted, commands ignored until end of transaction block
...gnored as a failed SQL statement. You are welcome to fail SQL statements all you want and PostgreSQL won't stop you.
Stay being in a transaction, but when you detect that the first SQL has failed, either rollback/re-start or commit/restart the transaction. Then you can continue failing as many S...
How to use ng-repeat for dictionaries in AngularJs?
...very similar to ng-repeat directive. The difference is that is will repeat all the HTML elements (including the tag it's defined on) up to the ending HTML tag where ng-repeat-end is placed (including the tag with ng-repeat-end).
Sample code (from a controller):
// ...
$scope.users = {};
$scope.us...