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How can I access and process nested objects, arrays or JSON?
I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)?
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Is there a standard sign function (signum, sgn) in C/C++?
I want a function that returns -1 for negative numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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Android dex gives a BufferOverflowException when building
When compiling a specific Android project, and only on my Windows machine, I get a java.nio.BufferOverflowException during from dex. The problem occurs both when using Eclipse and when using Ant.
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The modulo operation on negative numbers in Python
...but in C, if N ≥ 3, we get a negative number which is an invalid number, and we need to manually fix it up by adding 7:
int result = (2 - N) % 7;
return result < 0 ? result + 7 : result;
(See http://en.wikipedia.org/wiki/Modulo_operator for how the sign of result is determined for different la...
Quick-and-dirty way to ensure only one instance of a shell script is running at a time
What's a quick-and-dirty way to make sure that only one instance of a shell script is running at a given time?
40 Answers
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Passing command line arguments to R CMD BATCH
.... I am now at the point where I would like to pass an argument to the command, but am having some issues getting it working. If I do R CMD BATCH my_script.R blabla then blabla becomes the output file, rather than being interpreted as an argument available to the R script being executed.
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Datatype for storing ip address in SQL Server
...s (no, not even an INT32/INT(4), the numeric textual form that we all know and love (255.255.255.255) being just the display conversion of its binary content).
If you do it this way, you will want functions to convert to and from the textual-display format:
Here's how to convert the textual displa...
How to convert floats to human-readable fractions?
...y what you are asking for. Its based on the theory of continued fractions and very fast and fairly compact.
I have used versions of this customized for specific numerator and denominator limits.
/*
** find rational approximation to given real number
** David Eppstein / UC Irvine / 8 Aug 1993
**
*...
Simple Digit Recognition OCR in OpenCV-Python
...v2). It is just for learning purposes. I would like to learn both KNearest and SVM features in OpenCV.
3 Answers
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Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0
I opened an existing iOS project with Xcode6 beta6, and Xcode lists the following warning for both Storyboard and Xib files:
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