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To find whether a column exists in data frame or not
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edited Apr 28 '12 at 15:09
answered Apr 23 '12 at 7:03
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How to get the index of an item in a list in a single step?
...) operation, where n is Count.
If the item is not found, it will return -1
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Git: how to reverse-merge a commit?
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106
To create a new commit that 'undoes' the changes of a past commit, use:
$ git revert <comm...
When is it better to use an NSSet over an NSArray?
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Can PostgreSQL index array columns?
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184
Yes you can index an array, but you have to use the array operators and the GIN-index type.
E...
How to compute the sum and average of elements in an array?
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Find which commit is currently checked out in Git
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182
You have at least 5 different ways to view the commit you currently have checked out into your...
How do I find the time difference between two datetime objects in python?
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Skip first entry in for loop in python?
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13 Answers
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How to manually install an artifact in Maven 2?
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147
You need to indicate the groupId, the artifactId and the version for your artifact:
mvn insta...