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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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How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites
...answered Jul 5 '10 at 7:45
Sky SandersSky Sanders
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What is the difference between Digest and Basic Authentication?
What is the difference between Digest and Basic Authentication ?
4 Answers
4
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What's the difference between == and .equals in Scala?
What is the difference between == and .equals() in Scala, and when to use which?
5 Answers
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Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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What is the difference between concurrency and parallelism?
What is the difference between concurrency and parallelism?
37 Answers
37
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How to sort a list/tuple of lists/tuples by the element at a given index?
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@Stephen using itemgetter is faster and simpler: key=itemgetter(1) and at the beginning of the file: from operator import itemgetter
– Joschua
Mar 13 '13 at 20:08
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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
rsync: difference between --size-only and --ignore-times
I'm trying to understand what the difference is between two options
4 Answers
4
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In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
...oach would be to check how many digits are output by Integer.toHexString() and add a leading zero to each byte if needed. Something like this:
public static String toHexString(byte[] bytes) {
StringBuilder hexString = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
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