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How do I get the row count of a pandas DataFrame?
...[0].count()", "len(data.index)"],
xlabel="data rows"
)
EDIT: As @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
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Standard alternative to GCC's ##__VA_ARGS__ trick?
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It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
Unresolved external symbol on static class members
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dss539
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answered Oct 12 '08 at 7:49
Colin JensenColin Je...
What are the Dangers of Method Swizzling in Objective-C?
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I think this is a really great question, and it's a shame that rather than tackling the real question, most answers have skirted the issue and simply said not to use swizzling.
Using method sizzling is like using sharp knives in the kitchen. So...
How does the @property decorator work in Python?
...is just syntactic sugar; the syntax:
@property
def foo(self): return self._foo
really means the same thing as
def foo(self): return self._foo
foo = property(foo)
so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @foo.setter(), what you ...
How to use if statements in underscore.js templates?
...ue proposed in this answer is that you're stuck doing string interpolation all over again, which templates are supposed to solve for you. As of right now, _.template inserts a ; at the start of each compiled code tag. Thus, it can handle tags breaking between statements, but not inside of expression...
JSON serialization of Google App Engine models
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There is a small mistake in the code: Where you have "output[key] = to_dict(model)" it should be: "output[key] = to_dict(value)". Besides that it's perfect. Thanks!
– arikfr
Nov 7 '09 at 22:02
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What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
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It's usually to namespace (see later) and control the visibility of member functions and/or variables. Think of it like an object definition. The technical name for it is an Immediately Invoked Function Expression (IIFE). jQuery plug...
How to manually expand a special variable (ex: ~ tilde) in bash
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Using eval is a horrible suggestion, it's really bad that it gets so many upvotes. You will run into all sorts of problems when the variable's value contains shell meta characters.
– user2719058
Aug 31 '14 at 19:47
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What is the difference between a.getClass() and A.class in Java?
...getClass() will return the B class.
A.class evaluates to the A class statically, and is used for other purposes often related to reflection.
In terms of performance, there may be a measurable difference, but I won't say anything about it because in the end it is JVM and/or compiler dependent.
T...