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What is the difference between NaN and None?
...n reason to use NaN (over None) is that it can be stored with numpy's float64 dtype, rather than the less efficient object dtype, see NA type promotions.
# without forcing dtype it changes None to NaN!
s_bad = pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype...
Comparing object properties in c# [closed]
...oblems with overriding .Equals() because i'm trying to implement this on a base class that gets inherited... because I don't know the keys for the class this'll be run against, i can't implement a decent override for GetHasCode() (req'd when you override Equals()).
– nailitdown...
What is the difference between _tmain() and main() in C++?
...on unicode-ready (I prefer the term of unicode-ready to -aware), if it was based on char s before. If your application directly uses wchar_t then your application is unicode.
– paercebal
May 14 '10 at 16:49
...
Laravel: Get base url
... Exam: I have site in local: localhost/abc In Codeigniter: echo base_url(); => I get localhost/abc In Laravel: echo url(); => I get localhost/abc too.
– Nguyễn Thành Bồi
Nov 13 '14 at 3:24
...
How do you validate a URL with a regular expression in Python?
...{2}))+)(?:,(?:(?:[a-zA-Z\d$\-_.+!*'(),]|(?:%[a-f
A-F\d]{2}))+))*)?)(?:\?(?:base|one|sub)(?:\?(?:((?:[a-zA-Z\d$\-_.+!*'(
),;/?:@&=]|(?:%[a-fA-F\d]{2}))+)))?)?)?)|(?:(?:z39\.50[rs])://(?:(?:(?
:(?:(?:[a-zA-Z\d](?:(?:[a-zA-Z\d]|-)*[a-zA-Z\d])?)\.)*(?:[a-zA-Z](?:(?
:[a-zA-Z\d]|-)*[a-zA-Z\d])?))|(?:(...
Javascript Drag and drop for touch devices [closed]
... look at the code from June 30, 2011; my answer will make a lot more sense based on that version.
– E.Z. Hart
Nov 13 '14 at 2:13
...
If table exists drop table then create it, if it does not exist just create it
...plexity increases and locking functions in MySQL aren't safe for statement-based replication.
If the table data should survive table definition upgrade... For general case it's far more complex story about comparing table definitions to find out differences and produce proper ALTER ... statement, w...
How to implement the factory method pattern in C++ correctly
...t;
void registerType(QString name)
{
static_assert(std::is_base_of<T, TDerived>::value, "Factory::registerType doesn't accept this type because doesn't derive from base class");
_createFuncs[name] = &createFunc<TDerived>;
}
T* create(QString name) {
...
How to use the pass statement?
...ompileError(Exception):
pass
Similarly, classes intended as abstract base class often have an explicit empty __init__ or other methods that subclasses are supposed to derive. (e.g. pebl)
class _BaseSubmittingController(_BaseController):
def submit(self, tasks): pass
def retrieve(self,...
(![]+[])[+[]]… Explain why this works
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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