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What is the C# equivalent of NaN or IsNumeric?
What is the most efficient way of testing an input string whether it contains a numeric value (or conversely Not A Number)? I guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB...
Drop unused factor levels in a subsetted data frame
I have a data frame containing a factor . When I create a subset of this dataframe using subset or another indexing function, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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Why does the C preprocessor interpret the word “linux” as the constant “1”?
Why does the C preprocessor in GCC interpret the word linux (small letters) as the constant 1 ?
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How does Java Garbage Collection work with Circular References?
From my understanding, garbage collection in Java cleans up some objects if nothing else is 'pointing' to that object.
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jQuery Ajax POST example with PHP
I am trying to send data from a form to a database. Here is the form I am using:
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How to get the current branch name in Git?
I'm from a Subversion background and, when I had a branch, I knew what I was working on with "These working files point to this branch".
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Distinct by property of class with LINQ [duplicate]
I have a collection:
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How can I calculate the number of lines changed between two commits in git?
Is there any easy way to calculate the number of lines changed between two commits in git?
11 Answers
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Replace a character at a specific index in a string?
I'm trying to replace a character at a specific index in a string.
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When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
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