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When to use Cast() and Oftype() in Linq
...ly the elements that can safely be cast to type x.
Cast - will try to cast all the elements into type x. if some of them are not from this type you will get InvalidCastException
EDIT
for example:
object[] objs = new object[] { "12345", 12 };
objs.Cast<string>().ToArray(); //throws InvalidCas...
Create a variable name with “paste” in R?
...oss: a <- rnorm(1); a - eval(parse(text=paste(a))) does not return 0 usually.
– user10307643
Oct 7 '19 at 13:31
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Xml configuration versus Annotation based configuration [closed]
...nformation. But if you like JPA (I don't have any expirience with it), by all means, go for it.
In general:
If an annotation provides functionality and acts as a comment in and of itself, and doesn't tie the code down to some specific process in order to function normally without this annotation, ...
Best approach to real time http streaming to HTML5 video client
I'm really stuck trying to understand the best way to stream real time output of ffmpeg to a HTML5 client using node.js, as there are a number of variables at play and I don't have a lot of experience in this space, having spent many hours trying different combinations.
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Unique combination of all elements from two (or more) vectors
I am trying to create a unique combination of all elements from two vectors of different size in R.
5 Answers
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ASP.NET Web Site or ASP.NET Web Application?
...antly, it will come up with new names for the DLL files generated by pages all the time. That can lead to having several close copies of DLL files containing the same class name,
which will generate plenty of errors. The Web Site project was introduced with Visual Studio 2005, but it has turned o...
What is LDAP used for?
...e extremely fast read/query performance for a large scale of dataset. Typically you want to store only a small piece of information for each entry. The add/delete/update performance is relatively slower compared with read/query because the assumption is that you don’t do “update” that often.
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difference between throw and throw new Exception()
...w ex; throws the original exception but resets the stack trace, destroying all stack trace information until your catch block.
NEVER write throw ex;
throw new Exception(ex.Message); is even worse. It creates a brand new Exception instance, losing the original stack trace of the exception, as well...
Python - List of unique dictionaries
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If you need all values considered and not just the ID you can use list({str(i):i for i in L}.values()) Here we use str(i) to create a unique string that represents the dictionary which is used to filter the duplicates.
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Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
...s of simple selectors.
The :nth-child() pseudo-class counts elements among all of their siblings under the same parent. It does not count only the siblings that match the rest of the selector. Similarly, the :nth-of-type() pseudo-class counts siblings sharing the same element type, which refers to t...