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Define a lambda expression that raises an Exception
How can I write a lambda expression that's equivalent to:
6 Answers
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Fastest way to replace NAs in a large data.table
I have a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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Simple regular expression for a decimal with a precision of 2
What is the regular expression for a decimal with a precision of 2?
17 Answers
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Generate random numbers with a given (numerical) distribution
I have a file with some probabilities for different values e.g.:
13 Answers
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Can I set background image and opacity in the same property?
I can see in CSS references how to set image transparency and how to set a background image . But how can I combine these two in order to set a transparent background image?
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CSS Font Border?
With all the new CSS3 border stuff going on ( -webkit , ...) is it now possible to add a border to your font? (Like the solid white border around the blue Twitter logo). If not, are there any not-too-ugly hacks that will accomplish this in CSS/XHTML or do I still need to fire up Photoshop?
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How should I validate an e-mail address?
What's a good technique for validating an e-mail address (e.g. from a user input field) in Android? org.apache.commons.validator.routines.EmailValidator doesn't seem to be available. Are there any other libraries doing this which are included in Android already or would I have to use RegExp?
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Fastest way to check if a string matches a regexp in ruby?
What is the fastest way to check if a string matches a regular expression in Ruby?
7 Answers
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How to darken a background using CSS?
I have an element with text in it. Whenever I decrease the opacity, then I decrease the opacity of the WHOLE body. Is there any way I can just make the background-image darker, and not everything else?
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How to pip install a package with min and max version range?
I'm wondering if there's any way to tell pip, specifically in a requirements file, to install a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
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