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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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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...
STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...定义一个结构体来试试：[cpp]view plaincopystructa{char*pName;intm_a;} 引言
STL的map容器中，key的类型是不是随意的呢？
实践
编写测试代码
定义一个结构体来试试：
struct a
{
char* pName;
int m_a;
};
...
map<a, int> mp;
a ...
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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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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Checking if an instance's class implements an interface?
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As therefromhere points out, you can use class_implements(). Just as with Reflection, this allows you to specify the class name as a string and doesn't require an instance of the class:
interface IInterface
{
}
class TheClass implements IInterface
{
}
$interfaces = cl...
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...
How to suppress scientific notation when printing float values?
...cify how many digit after the . you wish to display, this depends on how small is the floating number). See this example:
>>> a = -7.1855143557448603e-17
>>> '{:f}'.format(a)
'-0.000000'
as shown above, default is 6 digits! This is not helpful for our case example, so instead we...
Compile time string hashing
... string length, and the compiler is not clever enough to elide the second call. Check other answers for possible fix for this problem.
– CygnusX1
Feb 27 '16 at 16:34
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How to detect the end of loading of UITableView
...htafoya's comment is right. If you want this code to detect end of loading all data from source, it wouldn't, but that's not the original question. This code is for detecting when all cells that are meant to be visible are displayed. willDisplayCell: used here for smoother UI (single cell usually di...