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How do I horizontally center an absolute positioned element inside a 100% width div? [duplicate]
In the example below, #logo is positioned absolutely and I need it to be horizontally centered within #header . Normally, I would do a margin:0 auto for relatively positioned elements but I am stuck here. Can someone show me the way?
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Convert column classes in data.table
I have a problem using data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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How to check with javascript if connection is local host?
I want to have a check in my javascript if the page loading up is on my local machine.
12 Answers
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Principal component analysis in Python
I'd like to use principal component analysis (PCA) for dimensionality reduction. Does numpy or scipy already have it, or do I have to roll my own using numpy.linalg.eigh ?
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Which SQL query is faster? Filter on Join criteria or Where clause?
Compare these 2 queries. Is it faster to put the filter on the join criteria or in the WHERE clause. I have always felt that it is faster on the join criteria because it reduces the result set at the soonest possible moment, but I don't know for sure.
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What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?
There are three assembly version attributes. What are differences? Is it ok if I use AssemblyVersion and ignore the rest?
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Regular expression for a hexadecimal number?
How do I create a regular expression that detects hexadecimal numbers in a text?
11 Answers
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Frequency table for a single variable
One last newbie pandas question for the day: How do I generate a table for a single Series?
4 Answers
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How to create a colored 1x1 UIImage on the iPhone dynamically?
I would like to create a 1x1 UIImage dynamically based on a UIColor.
6 Answers
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Remove empty elements from an array in Javascript
How do I remove empty elements from an array in JavaScript?
44 Answers
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