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Why does NULL = NULL evaluate to false in SQL server
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SQL NULL is not any different from IEEE floating point NaN, where you also have (NaN == NaN) == false && (NaN != Nan) == false && (NaN < NaN) == false && ... - because, well, if it's not a number, you just can't say much about i...
How to remove multiple indexes from a list at the same time? [duplicate]
... removes the slice starting at 2 and ending just before 6.
It isn't clear from your question whether in general you need to remove an arbitrary collection of indexes, or if it will always be a contiguous sequence.
If you have an arbitrary collection of indexes, then:
indexes = [2, 3, 5]
for index...
Difference: std::runtime_error vs std::exception()
... of the term).
std::runtime_error is a more specialized class, descending from std::exception, intended to be thrown in case of various runtime errors. It has a dual purpose. It can be thrown by itself, or it can serve as a base class to various even more specialized types of runtime error exceptio...
Dynamic instantiation from string name of a class in dynamically imported module?
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module = __import__(module, fromlist=[name]) only worked for me.
– umpirsky
Jan 9 '12 at 18:18
16
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How to access session variables from any class in ASP.NET?
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(Updated for completeness)
You can access session variables from any page or control using Session["loginId"] and from any class (e.g. from inside a class library), using System.Web.HttpContext.Current.Session["loginId"].
But please read on for my original answer...
I always use a...
Extract month and year from a zoo::yearmon object
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Having had a similar problem with data from 1800 to now, this worked for me:
data2$date=as.character(data2$date)
lct <- Sys.getlocale("LC_TIME");
Sys.setlocale("LC_TIME","C")
data2$date<- as.Date(data2$date, format = "%Y %m %d") # and it works
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Understanding the Gemfile.lock file
...lot whilst building an automated dependency update tool1. The below is far from definitive, but it's a good starting point for understanding the Gemfile.lock format. You might also want to check out the source code for Bundler's lockfile parser.
You'll find the following headings in a lockfile gene...
How do I pass variables and data from PHP to JavaScript?
...PHP, and I need its value in my JavaScript code. How can I get my variable from PHP to JavaScript?
19 Answers
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Sell me on const correctness
... be more of a pain than a help in C++. But then again, I'm coming at this from the python perspective: if you don't want something to be changed, don't change it. So with that said, here are a few questions:
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How can I connect to Android with ADB over TCP? [closed]
...ing in Hyper-V , and so I cannot connect directly via USB in the guest or from the host.
37 Answers
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