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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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curl : (1) Protocol https not supported or disabled in libcurl
I'm trying to install the Rails environments on Ubuntu 11.04. When I launch the command rvm install 1.9.2 --with-openssl-dir=/usr/local the following error is received:
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How to invoke a Linux shell command from Java
I am trying to execute some Linux commands from Java using redirection (>&) and pipes (|). How can Java invoke csh or bash commands?
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iPhone Simulator - Simulate a slow connection?
Is there a way to slow down the internet connection to the iPhone Simulator, so as to mimic how the App might react when you are in a slow spot on the cellular network?
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How do I access properties of a javascript object if I don't know the names?
Say you have a javascript object like this:
8 Answers
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Should I use string.isEmpty() or “”.equals(string)?
I'm usually testing this alongside a string == null , so I'm not really concerned about a null-safe test. Which should I use?
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c++11 Return value optimization or move? [duplicate]
I don't understand when I should use std::move and when I should let the compiler optimize... for example:
4 Answers
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Sorting multiple keys with Unix sort
I have potentially large files that need to be sorted by 1-n keys. Some of these keys might be numeric and some of them might not be. This is a fixed-width columnar file so there are no delimiters.
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STL中map容器使用自定义key类型报错详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
STL中map容器使用自定义key类型报错详解引言STL的map容器中，key的类型是不是随意的呢？实践编写测试代码定义一个结构体来试试：[cpp]view plaincopystructa{char*pName;intm_a;} 引言
STL的map容器中，key的类型是不是随意的呢？
实践
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Why should text files end with a newline?
I assume everyone here is familiar with the adage that all text files should end with a newline. I've known of this "rule" for years but I've always wondered — why?
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