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How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
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Swift - Split string over multiple lines
... some text
over multiple lines
"""
Older versions of Swift don't allow you to have a single literal over multiple lines but you can add literals together over multiple lines:
var text = "This is some text\n"
+ "over multiple lines\n"
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What are the rules about using an underscore in a C++ identifier?
...FC background, you'll probably use m_foo . I've also seen myFoo occasionally.
5 Answers
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What is a good regular expression to match a URL? [duplicate]
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I changed your expression a bit so it will work in all cases i need, including uri with http:// or www "/([^\s\.]+\.[^\s]{2,}|www\.[^\s]+\.[^\s]{2,})/gi"
– Ismael
Jan 14 '15 at 11:08
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“Large data” work flows using pandas
... one contains different fields, or do they have some records per file with all of the fields in each file?
Do you ever select subsets of rows (records) based on criteria (e.g. select the rows with field A > 5)? and then do something, or do you just select fields A, B, C with all of the records (a...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
... two beautiful aspects:
Divide and conquer: break the problem into two smaller problems.
Partition the elements in-place.
The short Haskell example demonstrates (1), but not (2). How (2) is done may not be obvious if you don't already know the technique!
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Favorite Django Tips & Features?
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This alleviates you from always type os.path.join() which gets annoying pretty fast: j = lambda filename: os.path.join(PROJECT_DIR, filename). Then you just need to type j("static").
– wr.
Ma...
How do I get an object's unqualified (short) class name?
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You can do this with reflection. Specifically, you can use the ReflectionClass::getShortName method, which gets the name of the class without its namespace.
First, you need to build a ReflectionClass instance, and then call the getShortName method of that instance:...
How to use timeit module
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The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...
Java - No enclosing instance of type Foo is accessible
...provide runtime arguments makes it a bother to use a main method. This was all I needed and exactly what I was looking to find.
– Abandoned Cart
Jul 27 '16 at 6:03
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