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Standardize data columns in R

I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages. 15 ...
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How to set default value to the input[type=“date”] [duplicate]

... @sheriffderek . This is not supported in all browsers, you need a jquery or similar fallback solution – jonah May 3 '17 at 2:49 ...
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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 ...
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Python __call__ special method practical example

I know that __call__ method in a class is triggered when the instance of a class is called. However, I have no idea when I can use this special method, because one can simply create a new method and perform the same operation done in __call__ method and instead of calling the instance, you can c...
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viewWillDisappear: Determine whether view controller is being popped or is showing a sub-view contro

...trollers property) has been updated by the time that viewWillDisappear is called. share | improve this answer | follow | ...
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How to disable back swipe gesture in UINavigationController on iOS 7

...ewDidDisappear, but works in method viewWillDisappear. On iOS7 it works in all of above mentioned methods. So try to use it in any other methods while working on the viewController, I confirm it works for me on iOS8 when I click on some button inside of the view. – Sihad Begovi...
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What are the rules for calling the superclass constructor?

What are the C++ rules for calling the superclass constructor from a subclass one? 10 Answers ...
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How do I initialize the base (super) class?

... and invoke their base class through super(), e.g. class X(object): def __init__(self, x): pass def doit(self, bar): pass class Y(X): def __init__(self): super(Y, self).__init__(123) def doit(self, foo): return super(Y, self).doit(foo) Because python knows about old- an...
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Curly braces in string in PHP

...nterpolation. From the manual: Complex (curly) syntax This isn't called complex because the syntax is complex, but because it allows for the use of complex expressions. Any scalar variable, array element or object property with a string representation can be included via this synta...
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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 ...