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How to find the length of a string in R
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As of 3.3.1 the base defaults are set to give nchar(NA) ## [1] NA : see nchar RDocumentation
– leerssej
Oct 11 '16 at 1:15
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Checking if a string can be converted to float in Python
...f you cared about performance (and I'm not suggesting you should), the try-based approach is the clear winner (compared with your partition-based approach or the regexp approach), as long as you don't expect a lot of invalid strings, in which case it's potentially slower (presumably due to the cost ...
What are the differences between struct and class in C++?
...2.2 in C++98 through C++11):
In absence of an access-specifier
for a base class, public is assumed
when the derived class is declared
struct and private is assumed when the class is declared class.
And just for completeness' sake, the more widely known difference between class and struct...
File Hash 扩展：文件哈希计算和 Base64 编码文件，sha256、sha512 哈希 ·...
... File Hash 扩展：文件哈希计算和 Base64 编码文件，sha256、sha512 哈希
File Hash 扩展
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函数
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Check if a value exists in ArrayList
...et so better to use later. In Java 8 we can use streams also to check item based on its equality or based on a specific property.
Java 8
CurrentAccount conta5 = new CurrentAccount("João Lopes", 3135);
boolean itemExists = lista.stream().anyMatch(c -> c.equals(conta5)); //provided equals and ha...
Java `final` method: what does it promise?
...You can't override it in your derived class, therefore it will do what the base class author intended.
http://download.oracle.com/javase/tutorial/java/IandI/final.html
Worth noting is the part where it suggests that methods called from constructors should be final.
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'setInterval' vs 'setTimeout' [duplicate]
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setInterval()
setInterval is a time interval based code execution method that has the native ability to repeatedly run specified script when the interval is reached. It should not be nested into its callback function by the script author to make it loop, since it loops ...
Why does base64 encoding require padding if the input length is not divisible by 3?
What is the purpose of padding in base64 encoding. The following is the extract from wikipedia:
3 Answers
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How to get current user, and how to use User class in MVC5?
...cation and authorization have changed for ASP.NET MVC 5. Now it's a Claims-based authentication with interfaces and generic repositories that you can use with EF or other provider (EF implementation comes as a default). Since GetUserId is an extension method stored at the bottom of Ass_Start\Identit...
Polymorphism with gson
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This is a bit late but I had to do exactly the same thing today. So, based on my research and when using gson-2.0 you really don't want to use the registerTypeHierarchyAdapter method, but rather the more mundane registerTypeAdapter. And you certainly don't need to do instanceofs or write adapt...