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Linux shell is very powerful. Sometimes I use it. But the long command prompts make me uncomfortable. This is my favorate command prompt: export PS1=" 阅读全文
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Introduction A list is an indexed set of objects, which can include different data type, even lists. Its power and utility are from its generality. In 阅读全文
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I build a folder in gitee library. I use picgo to help me upload the pics. At the same time, I want to make a copy for the blog files. I used git pull 阅读全文
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The knitr is an very useful tool to output a report file. Generally, I use knitr::kable(cars,format = "html") to output a html file. In most time, it 阅读全文
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The renv package is a new effort to bring project-local R dependency management to your projects. There are three commands to do it. ·renv::init()·, i 阅读全文
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后续代码不执行 原生 javascript 的 getElementById() 和 getElementsByTagName() 方法来操作指定的元素时，如果被操作的元素不存在，则浏览器会抛出错误，并终止代码的运行，更新影响其后的代码运行。为了避免上述情况的发生，所以在无法确定要操作的元素是否存在 阅读全文
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1.3.4.1 Automatic Drawing Layout>Energy>Starting positions relocation technique limitations results depend on the starting positions of vertices it st 阅读全文
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When I use the rstudio, it often prompts me a very long tip for me. It hinders me to write some comands. Thus, I use `export PS1=“$”` to short the tip 阅读全文
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This is my first time to use renv package. I want it can help me to keep the enivronment clean and robust. library(renv) When I run the command, which 阅读全文
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精英是社会的精华，在能力、见识、胆识、财产、文化素养等诸多方面超过大多数群众，对社会的发展有着极其重要影响和积极作用 君子，以行仁、行义为己任。君子也尚勇，但勇的前提必须是仁义，是事业的正当性。君子处事要恰到好处，要做到中庸。九三,君子终日乾乾,夕惕若厉,无咎。 武士，士分为武士和文士，文士出智武士 阅读全文