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Why does Math.Round(2.5) return 2 instead of 3?
In C#, the result of Math.Round(2.5) is 2.
15 Answers
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How can I find the number of days between two Date objects in Ruby?
How can I find the number of days between two Date objects?
10 Answers
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In C#, what happens when you call an extension method on a null object?
Does the method get called with a null value or does it give a null reference exception?
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Python loop that also accesses previous and next values
How can I iterate over a list of objects, accessing the previous, current, and next items? Like this C/C++ code, in Python?
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How to install node.js as windows service?
I have downloaded node.js executable. How can I run that executable as windows service?
I cannot use standard node.js installer, since I need to run multiple version of node.js concurrently.
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Replacement for “rename” in dplyr
I like plyr's renaming function rename . I have recently started using dplyr, and was wondering if there is an easy way to rename variables using a function from dplyr, that is as easy to use as to plyr's rename ?
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Batch file include external file for variables
I have a batch file and I want to include external file containing some variables (say configuration variables). Is it possible?
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How to split a column into two columns?
I have a data frame with one column and I'd like to split it into two columns, with one column header as ' fips' and the other 'row'
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LINQ Select Distinct with Anonymous Types
So I have a collection of objects. The exact type isn't important. From it I want to extract all the unique pairs of a pair of particular properties, thusly:
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How would you do a “not in” query with LINQ?
I have two collections which have property Email in both collections. I need to get a list of the items in the first list where Email does not exist in the second list. With SQL I would just use "not in", but I do not know the equivalent in LINQ. How is that done?
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