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How to return a part of an array in Ruby?
...very similar array-slicing syntax to Python. Here is the ri documentation for the array index method:
--------------------------------------------------------------- Array#[]
array[index] -> obj or nil
array[start, length] -> an_array or nil
array[ran...
MongoDB aggregation framework match OR
Is it possible to do an OR in the $match?
2 Answers
2
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How do I check if an integer is even or odd? [closed]
How can I check if a given number is even or odd in C?
31 Answers
31
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How to set or change the default Java (JDK) version on OS X?
...tents/Home
Pick the version you want to be the default (1.6.0_65-b14-462 for arguments sake) then:
export JAVA_HOME=`/usr/libexec/java_home -v 1.6.0_65-b14-462`
or you can specify just the major version, like:
export JAVA_HOME=`/usr/libexec/java_home -v 1.8`
Now when you run java -version you wil...
Depend on a branch or tag using a git URL in a package.json?
Say I've forked a node module with a bugfix and I want to use my fixed version, on a feature branch of course, until the bugfix is merged and released.
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Why are these constructs using pre and post-increment undefined behavior?
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C has the concept of undefined behavior, i.e. some language constructs are syntactically valid but you can't predict the behavior when the code is run.
As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my min...
what is “strict mode” and how is it used?
...ve been looking over the JavaScript reference on the Mozilla Developer Network, and I came across something called "strict mode" . I read it over and I'm having trouble understanding what it does. Can someone briefly explain (in general) what its purpose is and how it is useful?
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Extracting text OpenCV
...e elements (inspired from a LPD):
#include "opencv2/opencv.hpp"
std::vector<cv::Rect> detectLetters(cv::Mat img)
{
std::vector<cv::Rect> boundRect;
cv::Mat img_gray, img_sobel, img_threshold, element;
cvtColor(img, img_gray, CV_BGR2GRAY);
cv::Sobel(img_gray, img_sobel, ...
Base64 length calculation?
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Each character is used to represent 6 bits (log2(64) = 6).
Therefore 4 chars are used to represent 4 * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
The number of unused padding chars resulting from the roundin...
Why do we need tuples in Python (or any immutable data type)?
I've read several python tutorials (Dive Into Python, for one), and the language reference on Python.org - I don't see why the language needs tuples.
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