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The simplest possible JavaScript countdown timer? [closed]
Just wanted to ask how to create the simplest possible countdown timer.
3 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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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 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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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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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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CALayer with transparent hole in it
I have a simple view (left side of the picture) and i need to create some kind of overlay (right side of the picture) to this view. This overlay should have some opacity, so the view bellow it is still partly visible.
Most importantly this overlay should have a circular hole in the middle of it so i...
Display numbers with ordinal suffix in PHP
I want to display numbers as follows
15 Answers
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