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How to open, read, and write from serial port in C?

I am a little bit confused about reading and writing to a serial port. I have a USB device in Linux that uses the FTDI USB serial device converter driver. When I plug it in, it creates: /dev/ttyUSB1. ...
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Numpy first occurrence of value greater than existing value

I have a 1D array in numpy and I want to find the position of the index where a value exceeds the value in numpy array. 7 A...
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javascript: recursive anonymous function?

...ive the function a name, even when you're creating the function as a value and not a "function declaration" statement. In other words: (function foo() { foo(); })(); is a stack-blowing recursive function. Now, that said, you probably don't may not want to do this in general because there are som...
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?

I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
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Create an index on a huge MySQL production table without table locking

...ed to create an index on a ~5M rows MySQL table. It is a production table, and I fear a complete block of everything if I run a CREATE INDEX statement... ...
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How to darken a background using CSS?

...HOLE body. Is there any way I can just make the background-image darker, and not everything else? 8 Answers ...
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Javascript calculate the day of the year (1 - 366)

... Edit: The code above will fail when now is a date in between march 26th and October 29th andnow's time is before 1AM (eg 00:59:59). This is due to the code not taking daylight savings time into account. You should compensate for this: var now = new Date(); var start = new Date(now.getFullY...
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Difference between DateTime and Time in Ruby

What's the difference between DateTime and Time classes in Ruby and what factors would cause me to choose one or the other? ...
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Trees in Twitter Bootstrap [closed]

...g to work on creating a tree (like a directory tree) that uses as much CSS and as little JS as possible (only for states, etc), and I want to know if there are some good existing tree plugins for bootstrap or jquery-ui bootstrap . ...
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Is R's apply family more than syntactic sugar?

...regarding execution time and / or memory. 5 Answers 5 ...