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Select N random elements from a List in C#
I need a quick algorithm to select 5 random elements from a generic list. For example, I'd like to get 5 random elements from a List<string> .
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
...cript.
You could have multiple CREATE TABLE statements, separated by GO. It's a way of isolating one part of the script from another, but submitting it all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of code. I tend to use BEGIN and END a...
How to Decrease Image Brightness in CSS
...s in CSS. I searched a lot but all I've got is about how to change the opacity, but that makes the image more bright.
can anyone help me ?
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What are some (concrete) use-cases for metaclasses?
... Matplotlib. However, on occasion one wants to do interactive plotting. With only a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and...
How do you automatically set text box to Uppercase?
...at when the user starts typing in the text box for example railway , then it should be altered to capital letters like RAILWAY without the user having to press the Caps-lock button.
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Where to put model data and behaviour? [tl; dr; Use Services]
I am working with AngularJS for my latest project. In the documentation and tutorials all model data is put into the controller scope. I understand that is has to be there to be available for the controller and thus within the corresponding views.
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Reverting to a specific commit based on commit id with Git? [duplicate]
With git log , I get a list of commits that I have made so far.
4 Answers
4
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pdftk compression option
...elated (lossless, but may display slightly differently):
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dBATCH -dQUIET -sOutputFile=output.pdf input.pdf
Edit: I just discovered another option (for lossless compression), which avoids the nasty gs command. qpdf is ...
Clearing purchases from iOS in-app purchase sandbox for a test user
...mail address, password, secret question, secret answer, date of birth, and iTunes store country. You can put exactly the same data (including password) for tester+01@gmail.com and tester+02@gmail.com and you will have two test accounts. Finally, in your tester@gmail.com inbox you will receive two ...
What does the question mark operator mean in Ruby?
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It is a code style convention; it indicates that a method returns a boolean value.
The question mark is a valid character at the end of a method name.
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