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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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What is the meaning of the term arena in relation to memory?
I'm reading a book on memory as a programming concept. In one of the later chapters, the author makes heavy use of the word arena , but never defines it. I've searched for the meaning of the word and how it relates to memory, and found nothing. Here are a few contexts in which the author uses the...
How to “warm-up” Entity Framework? When does it get “cold”?
No, the answer to my second question is not the winter.
5 Answers
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Why do == comparisons with Integer.valueOf(String) give different results for 127 and 128?
...a striking difference here.
valueOf is returning an Integer object, which may have its values cached between -128 and 127. This is why the first value returns true - it's cached - and the second value returns false - 128 isn't a cached value, so you're getting two separate Integer instances.
It i...
LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的窗口将被包含在主窗口之下。在主窗口内的标题为LINGO Model – LINGO1的窗口是LINGO的默认模型窗口，建立的模型都都要在该窗口内编码实现。下面举两个例子。
例1.1 如何在LINGO中求解如下的LP问题：
在模型窗口中输入如下...
Setting PATH environment variable in OSX permanently
I have read several answers on how to set environmental variables on OSX as permanently.
6 Answers
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What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?
I'm trying to get a cross-plattform build system working using CMake. Now the software has a few dependencies. I compiled them myself and installed them on my system.
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What are Vertex Array Objects?
I am just starting to learn OpenGL today from this tutorial: http://openglbook.com/the-book/
I got to chapter 2, where I draw a triangle, and I understand everything except VAOs (is this acronym OK?). The tutorial has this code:
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What should I use Android AccountManager for?
I've seen AccountManager in the Android SDK and that it is used for storing account information. Thus, I cannot find any general discussion of what it is intended for. Does anyone know of any helpful discussions of what the intention behind AccountManager is and what it buys you? Any opinions of wha...
BCL (Base Class Library) vs FCL (Framework Class Library)
What's the difference between the two? Can we use them interchangeably?
6 Answers
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