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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...
Refresh a page using PHP
How can I refresh a page using PHP periodically? If I can not do it by PHP, what is the best recommended scenario?
13 Answe...
Django. Override save for model
...self._image_changed = True
# Or put whole logic in here
small = rescale_image(self.image,width=100,height=100)
self.image_small=SimpleUploadedFile(name,small_pic)
def get_image(self):
return self._image
image = property(get_image, set_image)
# this is ...
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 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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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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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...
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 ...