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Finding row index containing maximum value using R
Given the following matrix lets assume I want to find the maximum value in column two:
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rails 3 validation on uniqueness on multiple attributes
I use Rails 3.0.0.beta4
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MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
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How do you move a commit to the staging area in git?
If you want to move a commit to the staging area - that is uncommit it and move all of the changes which were in it into the staging area (effectively putting the branch in the state that it would have been in prior to the commit) - how do you do it? Or is it something that you can't do?
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MongoDB: How to query for records where field is null or not set?
I have an Email document which has a sent_at date field:
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What is the difference between encode/decode?
I've never been sure that I understand the difference between str/unicode decode and encode.
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Where does this come from: -*- coding: utf-8 -*-
Python recognizes the following as instruction which defines file's encoding:
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Create array of symbols
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The original answer was written back in September '11, but, starting from Ruby 2.0, there is a shorter way to create an array of symbols! This literal:
%i[address city state postal country]
will do exactly what you want.
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What does -XX:MaxPermSize do?
Specifically, why would it help to fix a PermGen OutOfMemoryError issue?
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Get TransactionScope to work with async / await
I'm trying to integrate async / await into our service bus.
I implemented a SingleThreadSynchronizationContext based on this example http://blogs.msdn.com/b/pfxteam/archive/2012/01/20/10259049.aspx .
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