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How to decide font color in white or black depending on background color?
...need to break the hex code into 3 pieces to get the individual red, green, and blue intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individ...
How to find list intersection?
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If order is not important and you don't need to worry about duplicates then you can use set intersection:
>>> a = [1,2,3,4,5]
>>> b = [1,3,5,6]
>>> list(set(a) & set(b))
[1, 3, 5]
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Fast permutation -> number -> permutation mapping algorithms
...you have n possibilities, so you can describe this with a number between 0 and n-1. For the position that the next element ends up at, you have n-1 remaining possibilities, so you can describe this with a number between 0 and n-2.
Et cetera until you have n numbers.
As an example for n = 5, consid...
How do you round a floating point number in Perl?
...f perldoc -q round
Does Perl have a round() function? What about ceil() and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3...
How can I scale the content of an iframe?
...ow can I scale the content of an iframe (in my example it is an HTML page, and is not a popup) in a page of my web site?
17...
Context switches much slower in new linux kernels
...e intel_idle driver ignores the user's BIOS configuration for the C-states and dances to its own tune. In other words, even if you completely disable all C states in your PC's (or server's) BIOS, this driver will still force them on during periods of brief inactivity, which are almost always happeni...
PHP server on local machine?
I'm trying to build a PHP site and I'm wanting to test my PHP files without uploading them to my host. Basically testing them on my own machine before I upload them. How do I do that?
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Is it better to call ToList() or ToArray() in LINQ queries?
...lare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
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Difference between MEAN.js and MEAN.io
... noticed that there are two different stacks with either their own website and installation methods: mean.js and mean.io. So I came up asking myself this question: "Which one do I use?".
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Vagrant reverse port forwarding?
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When you run vagrant ssh, it's actually using this underlying command:
ssh -p 2222 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o LogLevel=ERROR -o IdentitiesOnly=yes -i ~/.vagrant.d/insecure_private_key vagrant@127.0.0.1
SSH supports forwarding ports in the direction you ...