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How to remove a field completely from a MongoDB document?
Suppose this is a document. How do I remove " words " completely from all the documents in this collection? I want all documents to be without " words ":
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How do I grep for all non-ASCII characters?
... Homebrew's dupes library (enable using brew tap homebrew/dupes): brew install grep
– Bastiaan M. van de Weerd
Oct 22 '12 at 10:03
50
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How to determine whether a Pandas Column contains a particular value
...s)
Out[24]: True
As pointed out by @DSM, it may be more efficient (especially if you're just doing this for one value) to just use in directly on the values:
In [31]: s.values
Out[31]: array(['a', 'b', 'c'], dtype=object)
In [32]: 'a' in s.values
Out[32]: True
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What is a loop invariant?
...rograms. We make a single statement that we focus on proving true, and we call it the loop invariant. This organizes our logic. While we can just as well argue informally about the correctness of some algorithm, using a loop invariant forces us to think very carefully and ensures our reasoning is ai...
Java: Get last element after split
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@dotsid, I would leave this responsibility to the caller, hiding runtime exceptions is dangerous
– dfa
Jul 25 '09 at 12:27
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What is the difference between :first-child and :first-of-type?
...first child of the parent. So far the child elements we're looking at have all been divs, but bear with me, I'll get to that in a bit.
For now, the converse also holds true: any :first-child is also :first-of-type by necessity. Since the first child here is also the first div, it will match both ps...
Visual Studio 2013 IntelliSense stops working for ASP.NET MVC5 Controllers
... am facing a weird problem in my Visual Studio 2013 ASP.NET MVC 5 project. All of a sudden, the IntelliSense in the Controller classes of the MVC 5 project are not working at all.
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Casting a variable using a Type variable
...th a value of 1000, the compiler
// doesn't know the exact type so it will allow you to call any
// property or method on it, but will crash if it doesn't exist
dynamic value3 = Convert.ChangeType(value1, intType);
I've written the answer with generics, because I think it is a very likely sign of ...
Choice between vector::resize() and vector::reserve()
I am pre-allocating some memory to my a vector member variable. Below code is minimal part
4 Answers
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knitr Markdown highlighting in Emacs?
...r the former you need polymode and for the latter markdown.el. Besides, if all you want is to just switch the ESS engine from Sweave to knitr (without highlighting!), there is no need to go through all the complication of this article, just add (setq ess-swv-processor 'knitr) in you init file.
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