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How to decide font color in white or black depending on background color?
I want to show some images like this example
22 Answers
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What is the most efficient/elegant way to parse a flat table into a tree?
...ame table too. Read "Trees and Hierarchies in SQL for Smarties" by Joe Celko for a lot more information on these designs.
I usually prefer a design called Closure Table (aka "Adjacency Relation") for storing tree-structured data. It requires another table, but then querying trees is pretty easy.
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How do I use the nohup command without getting nohup.out?
...'re using nohup, that probably means you want to run the command in the background by putting another & on the end of the whole thing:
nohup command >/dev/null 2>&1 & # runs in background, still doesn't create nohup.out
On Linux, running a job with nohup automatically closes it...
How to draw a circle with text in the middle?
I found this example on stackoverflow:
17 Answers
17
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Finding the direction of scrolling in a UIScrollView?
...ave a UIScrollView with only horizontal scrolling allowed, and I would like to know which direction (left, right) the user scrolls. What I did was to subclass the UIScrollView and override the touchesMoved method:
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bundle install returns “Could not locate Gemfile”
I'm new to Rails and am currently working through a guide.
The guide states:
9 Answers
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Regex, every non-alphanumeric character except white space or colon
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Tudor ConstantinTudor Constantin
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Finding the type of an object in C++
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dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime check to ensure the val...
How to print number with commas as thousands separators?
...ld I go about doing this? I have seen many examples on Google, but I am looking for the simplest practical way.
26 Answers
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Sort a list by multiple attributes?
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A key can be a function that returns a tuple:
s = sorted(s, key = lambda x: (x[1], x[2]))
Or you can achieve the same using itemgetter (which is faster and avoids a Python function call):
import operator
s = sorted(s, key =...