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How do you delete a column by name in data.table?
...hod 3 (could then assign to df3,
df3[, !"foo"]
though if you were actually wanting to remove column "foo" from df3 (as opposed to just printing a view of df3 minus column "foo") you'd really want to use Method 1 instead.
(Do note that if you use a method relying on grep() or grepl(), you need ...
How to add Web API to an existing ASP.NET MVC 4 Web Application project?
...are that I need a controller deriving from ApiController, but that's about all I know.
9 Answers
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pycharm convert tabs to spaces automatically
... giving errors everywhere because it can't convert tabs to spaces automatically is there a way to achieve this.
7 Answers
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Strings as Primary Keys in SQL Database [closed]
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Technically yes, but if a string makes sense to be the primary key then you should probably use it. This all depends on the size of the table you're making it for and the length of the string that is going to be the primary key (lo...
Why wasn't PyPy included in standard Python?
...e JIT compilation and lower memory footprint greatly improve the speeds of all Python code?
6 Answers
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What is a ViewModelLocator and what are its pros/cons compared to DataTemplates?
...ing them from a dependency injection (DI) container. This happens automatically when the container is asked to provide (resolve) an instance of the View class. The container injects the ViewModel into the View by calling a constructor of the View which accepts a ViewModel parameter; this scheme is c...
What do
...hat they're subclasses of a generic function type (From) => To, but that's all it says. Um, what? Maybe there's documentation somewhere, but search engines don't handle "names" like "
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What is the proper way to check for existence of variable in an EJS template (using ExpressJS)?
...S 2.3.4 EDIT: using locals in place of this works
– X_Trust
Feb 9 '16 at 21:21
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C++ Tuple vs Struct
... not the purpose of this discussion so I won't dive into the detail.
We all know that writing a == or < or > operator for every single struct definition will be a painful and buggy task. Let replace our custom comparator using std::tie and rerun our benchmark.
bool operator<(const Str...
Hg: How to do a rebase like git's rebase
...er mq nor rebase are enabled by default in mercurial: because mercurial is all about indelible changesets. When I work in the manner you're describing, which is nearly daily, here's the pattern I take:
1. Start working on a new feature:
$ hg clone mainline-repo newfeature-123
do a few commits (M, ...