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Python timedelta in years
...een since some date. Currently I've got timedelta from datetime module and I don't know how to convert it to years.
16 ...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... most applications. However, if you need to support double-byte languages and you only have single-byte support in your database schema it's really expensive to go back and modify throughout your application.
The cost of migrating one application from varchar to nvarchar will be much more than t...
How to check if object (variable) is defined in R?
...een created by a queuing system. These can possibly be addressed with "ls" and its argument "pattern" that expects a regular expression.
The "exists" function could be reimplemented that way as
exists <-function(variablename) {
#print(ls(env=globalenv()))
return(1==length(ls(pattern=paste...
Unique ways to use the Null Coalescing operator [closed]
I know the standard way of using the Null coalescing operator in C# is to set default values.
16 Answers
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Why is string concatenation faster than array join?
...owsers have also optimized string concatenation, so Safari, Opera, Chrome, and Internet Explorer 8 also show better performance using the plus operator. Internet Explorer prior to version 8 didn’t have such an optimization, and so the array technique is always faster than the plus operator.
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How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
...eveloper to generate an ER diagram for my DB tables but I am new to Oracle and this tool.
8 Answers
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Differences between socket.io and websockets
What are the differences between socket.io and websockets in
node.js?
Are they both server push technologies?
The only differences I felt was,
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Generate random numbers with a given (numerical) distribution
... You can then use the rvs() method of the distribution object to generate random numbers.
As pointed out by Eugene Pakhomov in the comments, you can also pass a p keyword parameter to numpy.random.choice(), e.g.
numpy.random.choice(numpy.arange(1, 7), p=[0.1, 0.05, 0.05, 0.2, 0.4, 0.2])
If you a...
How do I compare two strings in Perl?
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See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary eq returns true if the left argument is stringwise equal to the right argument.
Binary ne returns true if the left argument is stringwise not equal to the right argument....
dispatch_after - GCD in Swift?
I've gone through the iBook from Apple, and couldn't find any definition of it:
24 Answers
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