R on Dr. Hui Lin

Learning ggmap

linhui@pric.org.cn (Dr. Hui Lin (林辉)) — Fri, 31 Mar 2017 14:24:00 +0000

This is a document for myself to review ggmap package, and how to get quick start.

ggmap is powerful map plot package in R. Compared with maps package, plots exported from ggmaps are elegant.

Two steps to plot a map: plot a map raster, decorate the base map with your own data.

Step 1: download your base map
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You need to know the location you will plot. Define location in two ways showing below:

Learning ggplot2

linhui@pric.org.cn (Dr. Hui Lin (林辉)) — Fri, 31 Mar 2017 14:12:00 +0000

本课程介绍三种R语言的绘图工具包：plot,qplot,ggplot。三种绘图包的能够和语法均不相同。 plot命令是R语言自带的绘图命令，绘图效果简单，适宜数据分析时绘图。 qplot命令是R语言初级绘图语言包，能够提供符合出版物标准的简单绘图。得到的图形大方美观。

Lesson: Regression Models Introduction
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制图：plot(jitter(child,4) ~ parent,galton)

建立回归函数：使用函数lm(linear model)，例如：

regrline <- lm(child~parent, galton)

建立回归函数之后，使用abline(add straight lines to a plot)函数将回归函数在图表中画出，例如

abline(regrline, lwd = 3, col = "red")
#lwd = line width, col = line color

画出直线之后可以使用函数summary查看回归函数的各类参数包括残差，系数，相关系数等等。

qplot
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qplot is a basic function in ggplot2 package. It provides some basic plots (e.g. points, smooth, boxplot) for users to learn their database generally.

Learning R in Kaggle

linhui@pric.org.cn (Dr. Hui Lin (林辉)) — Wed, 22 Mar 2017 12:35:00 +0000

I’m learning data analysis and explore in R following the tutorial posted in Kaggle

Here are some sentences I found it useful.

train <- read.csv('../input/train.csv', stringsAsFactors = F)

This is how to read csv files. Also, use read.delim(), read.delim2() to read txt file.read documentation

stringAsFactors is a useful factor. Here we do not want to use the headers as factors.

str(dataframe) use this to check data. Also if you use R Studio, use view(dataframe) to check data.

Learning R using Swirl

linhui@pric.org.cn (Dr. Hui Lin (林辉)) — Mon, 20 Feb 2017 20:30:00 +0000

用Swirl学习R语言，Learn R, in R
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how to import data (read function) how to manipulate data wit dplyr

lesson: Getting and Cleaning Data
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我们可以使用read.csv函数来导入数据。具体查看?read.csv，例子

#set a path to csv file
path2csv <-"E:/R-3.3.2/library/swirl/Courses/Getting_and_Cleaning_Data/Manipulating_Data_with_dplyr/2014-07-08.csv"

#use read.csv to read the csv file
mydf<-read.csv(path2csv,stringsAsFactors = FALSE)
#stringsAsFactors: logical: should character vectors be converted to factors?

使用dim()查看数据的行列情况

R basics

linhui@pric.org.cn (Dr. Hui Lin (林辉)) — Sun, 19 Feb 2017 22:23:00 +0000

R语言学习笔记
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这里是关于一些R语言的语法备忘 Learning Website

Unit 1 Assignment and basic calculation
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myapples = 3

myapples <- 3

+, -, *, /, ^

%% means the remainder.

Unit 2 Vectors
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combine function: c()

R on Dr. Hui Lin

Learning ggmap

Step 1: download your base map #

Learning ggplot2

Lesson: Regression Models Introduction #

qplot #

Learning R in Kaggle

Learning R using Swirl

用Swirl学习R语言，Learn R, in R #

lesson: Getting and Cleaning Data #