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How to append rows to an R data frame
...NTO, it has to REINDEX, which is O(n), where n is the number of rows. This means that insert into a SQL database one row at a time is O(n^2). SQLite can be very fast, if you insert a whole data.frame at once, but it's not the best at growing line by line.
– Julian Zucker
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Understanding the transclude option of directive definition?
...le container tag (like div or span) with the ng-transclude attribute. This means that the following code in your template should include all content
<div class="something"> This is my directive content <div class="something" ng-transclude></div></div>
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How to put a unicode character in XAML?
...l Studio are
automatically saved in the Unicode UTF-8 file format, which means that
most special characters, such as accent marks, are encoded correctly.
However, there is a set of commonly-used special characters that are
handled differently. These special characters follow the World Wide
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Bulk package updates using Conda
...o differs from conda search --outdated in that it runs through the solver, meaning some packages that have newer versions may not be updated if other packages have dependency restrictions (or, for example, conda update --all won't update from Python 2.7 to Python 3.4).
– asmeur...
CSS :after not adding content to certain elements
... some elements at all.
It is not clear at all what “replaced element” means, and the meaning appears to have changed somewhat. It is often interpreted as meaning the same as empty element (an element with EMPTY declared content, i.e. an element that cannot have any content), but CSS 2.1 itself ...
What is the Comonad typeclass in Haskell?
...there's a good chance that we're dealing with a comonad" .... So does that mean that fragment shaders are comonadic?
– Sam Kellett
Mar 17 '15 at 12:12
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How to validate an email address using a regular expression?
...involves sending that address a message that includes a confirmation token meant to be entered on the same web page as was the address.
Confirmation tokens are the only way to know you got the address of the person entering it. This is why most mailing lists now use that mechanism to confirm sign-...
Reordering of commits
...g to assume you want to leave commit c on branch A, and that you really do mean you want to move the other commits to the other branches, rather than merging, since merges are straightforward. Let's start by manipulating branch A.
git rebase -i <SHA1 of commit a>^ branchA
The ^ means the pr...
All falsey values in JavaScript
What are the values in JavaScript that are 'falsey' , meaning that they evaluate as false in expressions like if(value) , value ? and !value ?
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Popstate on page's load in Chrome
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Wouldn't that if always evaluate to false? I mean, window.history.ready is always true.
– Andriy Drozdyuk
Jan 30 '12 at 18:55
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