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C# 'is' operator performance
... answered Mar 26 '09 at 16:09
Andrew HareAndrew Hare
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How to get item's position in a list?
I am iterating over a list and I want to print out the index of the item if it meets a certain condition. How would I do this?
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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must appear in the GROUP BY clause or be used in an aggregate function
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To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname, m.wmname, t.mx
FROM (
SELECT cname, MAX(avg) AS mx
FROM makerar
GROUP BY cname
) t JOIN makerar m ON m.cname = t....
How can I use numpy.correlate to do autocorrelation?
I need to do auto-correlation of a set of numbers, which as I understand it is just the correlation of the set with itself.
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How to vertically center a container in Bootstrap?
... for a way to vertically center the container div inside the jumbotron and to set it in the middle of the page.
9 Answ...
Move branch pointer to different commit without checkout
...ch pointer of a checked out branch, one can use the git reset --hard command. But how to move the branch pointer of a not-checked out branch to point at a different commit (keeping all other stuff like tracked remote branch)?
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Default parameters with C++ constructors [closed]
...efault parameters, so long as the parameters make sense. Classes in the standard use them as well, which speaks in their favor.
One thing to watch out for is if you have defaults for all but one parameter, your class can be implicitly converted from that parameter type. Check out this thread for ...
What is the best way to tell if a character is a letter or number in Java without using regexes?
What is the best and/or easiest way to recognize if a string.charAt(index) is an A-z letter or a number in Java without using regular expressions? Thanks.
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Git reset --hard and push to remote repository
I had a repository that had some bad commits on it (D, E and F for this example).
5 Answers
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