In this blog post I share some lesser-known (at least I believe they are) tricks that use mainly functions from dplyr. Removing unneeded columns Did you know that you can use - in front of a column name to remove it from a data frame? mtcars %>% sele…

purrr is package that extends R's functional programming capabilities. It brings a lot of new stuff to the table and in this post I show you some of the most useful (at least to me) functions included in purrr. Getting rid of loops with map() library…

dplyr包是Hadley Wickham的新作,主要用于数据清洗和整理,该包专注dataframe数据格式,从而大幅提高了数据处理速度,并且提供了与其它数据库的接口:tidyr包的作者是Hadley Wickham, 该包用于"tidy"你的数据,这个包常跟dplyr结合使用. 本文将介绍dplyr包的下述五个函数用法: 筛选: filter() 排列: arrange() 选择: select() 变形: mutate() 汇总: summarise() 分组: group_by(…

前两次的总结:testng annotation生命周期 http://www.cnblogs.com/tobecrazy/p/4579414.html testng.xml的使用和基本配置http://www.cnblogs.com/tobecrazy/p/4582173.html 在前两次的总结中,了解了一些testng基础的用法,今天了解一下使用参数的trick和使用reportng生成漂亮的测试报告 Testng 传递参数的tricks 在 http://www.cnblogs.com/…

How to Train a GAN? Tips and tricks to make GANs work 转自:https://github.com/soumith/ganhacks While research in Generative Adversarial Networks (GANs) continues to improve the fundamental stability of these models, we use a bunch of tricks to train th…

dplyr是由Hadley Wickham主持开发和维护的一个主要针对数据框快速计算.整合的函数包,同时提供一些常用函数的高速写法以及几个开源数据库的连接.此包是plyr包的深化功能包,其名字中的字母“d”即来源于data frame,以示其专注于数据框数据的整理和操作.我们将在本章中着重介绍一些数据处理方面的常用功能函数. 1.1管道函数 在前面的简介中,我们计算了cran上的可用的函数包的数量: > contrib.url("http://mirrors.xmu.edu.cn/CRAN…

matlab tips and tricks and ... page overview: I created this page as a vectorization helper but it grew to become my annotated Matlab reading cache. In order to motivate the DSP people out there, I am showing below how one can apply a window and scal…

1.简介 在我们数据分析的实际应用中,我们可能会花费大量的时间在数据清洗上,而如果使用 R 里面自带的一些函数(base 包的 transform 等),可能会觉得力不从心,或者不是很人性化.好在我们有其他选择.这里我们介绍 dplyr 包. 首先加载包: install.packages("dplyr") library(dplyr) 单表操作函数(one table verbs)如下: filter: 保留满足条件的行 select: 使用列名选出列 arrange: 对数据的所有…

LoadRunner AJAX TruClient协议Tips and Trickshttp://automationqa.com/forum.php?mod=viewthread&tid=2851&fromuid=2…

原文:C# Tips & Tricks: Weak References - When and How to Use Them Sometimes you have an object which is very large and needed multiple times, but not constantly, throughout your application. For example a huge lookup table, or the contents of a large f…