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Simple Digit Recognition OCR in OpenCV-Python

...stand some of the features at end) 2) Since I knew, without understanding all those features, it is difficult to do that method. I tried some other papers, but all were a little difficult for a beginner. So I just decided to take all the pixel values as my features. (I was not worried about accura...
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Difference between a theta join, equijoin and natural join

... A theta join allows for arbitrary comparison relationships (such as ≥). An equijoin is a theta join using the equality operator. A natural join is an equijoin on attributes that have the same name in each relationship. Additionally,...
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How should I print types like off_t and size_t?

...6, some_uint16_t); They are listed in the manpage of inttypes.h. Personally, I would just cast the values to unsigned long or long like another answer recommends. If you use C99, then you can (and should, of course) cast to unsigned long long or long long and use the %llu or %lld formats respect...
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How to search a specific value in all tables (PostgreSQL)?

... at 11:55 Mike Sherrill 'Cat Recall'Mike Sherrill 'Cat Recall' 78.5k1616 gold badges103103 silver badges156156 bronze badges ...
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Count how many files in directory PHP

...n you include other directories within that directories and so on to count all files and exclude directories from the count? – The Bumpaster Jul 2 '16 at 13:40 1 ...
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Reference: What is variable scope, which variables are accessible from where and what are “undefined

... be in the global scope in a.php doesn't necessarily mean they are, it actually depends on which context that code is included/executed in. What about functions inside functions and classes? Every new function declaration introduces a new scope, it's that simple. (anonymous) functions inside func...
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OS X10.9 环境下部署 QT5.3.1 常见的编译问题 - 更多技术 - 清泛网 - 专注C/C++及内核技术

...件中加入对应的SDK版本: 1 QMAKE_MAC_SDK = macosx10.9 3、:-1: error: [ui_mainwindow.h] Trace/BPT trap: 5 dyld: Library not loaded: /work/build/______________________________PADDING______________________________/lib/QtCore.framework/Versio...
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What is the difference between linear regression and logistic regression?

...e, and greater than 1 whereas probability can not. As regression might actually produce probabilities that could be less than 0, or even bigger than 1, logistic regression was introduced. Source: http://gerardnico.com/wiki/data_mining/simple_logistic_regression Outcome In linear regression, the...
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How to filter a dictionary according to an arbitrary condition function?

... And here is a good explanation why the function call dict() is slower than the constructor/literal syntax {} doughellmann.com/2012/11/… – dorvak Jul 10 '13 at 9:37 ...
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Python constructors and __init__

Why are constructors indeed called "Constructors"? What is their purpose and how are they different from methods in a class? ...