Chapter 1 Rで遊ぶ

1.2 簡単な計算

In [1]:
123 + 456
Out[1]:
579
In [2]:
123 * 456 - 987 / (654 + 321)
Out[2]:
56086.9876923077
In [3]:
pi
Out[3]:
3.14159265358979
In [4]:
print(pi)

[1] 3.141593
In [5]:
print(pi, digits = 16)

[1] 3.141592653589793
In [6]:
x <- 12345
x
Out[6]:
12345
In [7]:
print(pi)
pi <- 3
print(pi)
rm(pi)
print(pi)

[1] 3.141593
[1] 3
[1] 3.141593
In [8]:
exp(1)
Out[8]:
2.71828182845905

1.4 データの入力

In [9]:
height <- c(168.5, 172.8, 159.0)
weight <- c(69.5, 75.0, 56.5)
In [10]:
weight / (height / 100)^2
Out[10]:
  1. 24.4785108612385
  2. 25.1173482510288
  3. 22.3487994936909
In [11]:
library(pipeR)

Warning message:
: package ‘pipeR’ was built under R version 3.2.4
In [12]:
(weight / (height / 100)^2) %>>% round
Out[12]:
  1. 24
  2. 25
  3. 22
In [13]:
(weight / (height / 100)^2) %>>% round(1)
Out[13]:
  1. 24.5
  2. 25.1
  3. 22.3

1.5 データフレーム

In [14]:
X <- data.frame(height, weight)
X
Out[14]:
heightweight
1168.5 69.5
2172.8 75.0
3159.0 56.5
In [15]:
X$height
Out[15]:
  1. 168.5
  2. 172.8
  3. 159
In [16]:
X$sex <- c("M", "M", "F")
X
Out[16]:
heightweightsex
1168.569.5 M
2172.875 M
3159 56.5F
In [17]:
X$BMI <- with(weight / (height / 100)^2, data = X) %>>% round(0)
X
Out[17]:
heightweightsexBMI
1168.569.5 M 24
2172.875 M 25
3159 56.5F 22

1.6 ファイルの読み書きと文字コード

In [18]:
dir(".")
Out[18]:
'Chap01.ipynb'
In [19]:
write.csv(X, "X.csv", quote = FALSE, row.names = FALSE, fileEncoding = "UTF-8", eol = "\r\n")
In [20]:
dir(".")
Out[20]:
  1. 'Chap01.ipynb'
  2. 'X.csv'
In [21]:
XX <- read.csv("X.csv")
XX
Out[21]:
heightweightsexBMI
1168.569.5 M 24
2172.875 M 25
3159 56.5F 22
In [22]:
XXX <- read.csv("http://okumuralab.org/~okumura/stat/data/coal.csv")
str(XXX)

'data.frame':	191 obs. of  7 variables:
 $ Day             : Factor w/ 8 levels "Fri","Frj","Mon",..: 4 7 4 3 4 6 3 6 8 4 ...
 $ Date            : int  15 19 20 22 24 6 10 20 22 12 ...
 $ Month           : Factor w/ 12 levels "April","Aug",..: 8 2 3 3 1 9 9 9 3 8 ...
 $ Year            : int  1851 1851 1851 1851 1852 1852 1852 1852 1852 1853 ...
 $ Day_of_year     : int  74 231 354 356 115 127 131 141 357 71 ...
 $ Interval_days   : int  NA 157 123 2 124 12 4 10 216 80 ...
 $ Number_of_deaths: int  61 35 52 13 12 22 65 36 10 10 ...

1.7 図の描き方

In [1]:
library(ggplot2)

Warning message:
“package ‘ggplot2’ was built under R version 3.2.4”
In [2]:
options(repr.plot.height = 4, repr.plot.width = 4)
In [3]:
x <- rnorm(1000000)
In [4]:
hist(x)
In [5]:
library("Cairo")
In [6]:
Cairo(type = "raster")
CairoFonts(regular = "IPAexGothic") # Mac
ggplot(data.frame(x = x), aes(x = x)) + 
    geom_histogram(binwidth = 0.5, boundary = 0.5, fill = "gray", colour = "black") + 
    theme_bw() + 
    theme(plot.title = element_text(family = "IPAexGothic")) + # Win
    scale_x_continuous(breaks = seq(-4, 4, 2)) + 
    scale_y_continuous(labels = scales::comma, breaks = c(50000, 150000)) + 
    ylab("Frequency") + 
    labs(title = "ヒストグラムの例")
dev.off()
pdf: 2

1.8 パッケージの例: Excelファイルを読む

In [33]:
library(readxl)

Warning message:
: package ‘readxl’ was built under R version 3.2.4
In [34]:
d <- read_excel("test.xlsx")
str(d)

Classes ‘tbl_df’, ‘tbl’ and 'data.frame':	5 obs. of  3 variables:
 $ Num : num  1 2 3 4 5
 $ Text: chr  "A" "B" "C" "D" ...
 $ Date: POSIXct, format: "2016-01-01" "2016-02-01" ...
In [37]:
print(d)

  Num Text       Date
1   1    A 2016-01-01
2   2    B 2016-02-01
3   3    C 2016-03-01
4   4    D 2016-04-01
5   5    E 2016-05-01
In [7]:
devtools::session_info()

Session info -------------------------------------------------------------------
Packages -----------------------------------------------------------------------

 setting  value                       
 version  R version 3.2.3 (2015-12-10)
 system   x86_64, darwin13.4.0        
 ui       X11                         
 language (EN)                        
 collate  ja_JP.UTF-8                 
 tz       Asia/Tokyo                  
 date     2016-09-23                  

 package    * version date       source                            
 Cairo      * 1.5-9   2015-09-26 CRAN (R 3.2.0)                    
 colorspace   1.2-6   2015-03-11 CRAN (R 3.2.0)                    
 crayon       1.3.2   2016-06-28 CRAN (R 3.2.5)                    
 devtools     1.12.0  2016-06-24 CRAN (R 3.2.5)                    
 digest       0.6.10  2016-08-02 CRAN (R 3.2.5)                    
 evaluate     0.9     2016-04-29 CRAN (R 3.2.5)                    
 ggplot2    * 2.1.0   2016-03-01 CRAN (R 3.2.4)                    
 gtable       0.2.0   2016-02-26 CRAN (R 3.2.3)                    
 IRdisplay    0.4.4   2016-08-02 CRAN (R 3.2.5)                    
 IRkernel     0.7     2016-09-22 Github (IRkernel/IRkernel@16ef3ed)
 jsonlite     1.1     2016-09-14 cran (@1.1)                       
 magrittr     1.5     2014-11-22 CRAN (R 3.2.0)                    
 memoise      1.0.0   2016-01-29 CRAN (R 3.2.3)                    
 munsell      0.4.3   2016-02-13 CRAN (R 3.2.3)                    
 pbdZMQ       0.2-4   2016-09-22 CRAN (R 3.2.3)                    
 plyr         1.8.3   2015-06-12 CRAN (R 3.2.0)                    
 R6           2.1.2   2016-01-26 CRAN (R 3.2.3)                    
 Rcpp         0.12.4  2016-03-26 CRAN (R 3.2.4)                    
 repr         0.9     2016-07-24 CRAN (R 3.2.5)                    
 scales       0.4.0   2016-02-26 CRAN (R 3.2.3)                    
 stringi      1.0-1   2015-10-22 CRAN (R 3.2.0)                    
 stringr      1.0.0   2015-04-30 CRAN (R 3.2.0)                    
 uuid         0.1-2   2015-07-28 CRAN (R 3.2.0)                    
 withr        1.0.1   2016-02-04 CRAN (R 3.2.3)