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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
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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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What does git push -u mean?
I have two different versions of git.
In the 1.6.2 version, git push does not have the -u option. It only appears in the 1.7.x version.
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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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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
Is there a cleaner way to do something like this?
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What does -XX:MaxPermSize do?
Specifically, why would it help to fix a PermGen OutOfMemoryError issue?
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How does OpenID authentication work?
I am a little curious to know about how OpenID authentication works.
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