getwd()## [1] "C:/Users/dell/Desktop/Teaching"#setwd()
dir(path="C:/Users/dell\\Desktop/")## [1] "1.png"
## [2] "2.png"
## [3] "5128OS_09_01.jpg"
## [4] "adult.data.txt"
## [5] "airline.sas7bdat"
## [6] "Analytics decisionstats.com Audience Overview 20110617-20120717.csv"
## [7] "AnalyticsforCEOs.docx"
## [8] "basicR.html"
## [9] "basicR.R"
## [10] "BigDiamonds.csv"
## [11] "BigDiamonds.csv.zip"
## [12] "Boston.csv"
## [13] "Cars.sav"
## [14] "casestudy"
## [15] "ccFraud.csv"
## [16] "ccFraud.zip"
## [17] "Certificate Doc.docx"
## [18] "CmapServer Download _ Cmap.html"
## [19] "CmapServer Download _ Cmap_files"
## [20] "Coxcombs.jpg"
## [21] "creditcardsrevo.R"
## [22] "creditcardsrevo.spin.R"
## [23] "creditcardsrevo.spin.Rmd"
## [24] "cricketparsing.R"
## [25] "CTujsdZUkAEo0a4.jpg"
## [26] "data input.R"
## [27] "data_input.html"
## [28] "datamining.html"
## [29] "datamining.R"
## [30] "dataq.html"
## [31] "dataq.R"
## [32] "dataqualityinR.html"
## [33] "dataqualityinR.R"
## [34] "datatable"
## [35] "datatablerevised.html"
## [36] "datatablerevised.R"
## [37] "day8 session 4.fbr"
## [38] "day9 session 1.fbr"
## [39] "desktop.ini"
## [40] "Dropbox.lnk"
## [41] "exam.html"
## [42] "exam.R"
## [43] "ie_data.xls"
## [44] "lastsave.txt"
## [45] "lastsave2"
## [46] "library.docx"
## [47] "Minard.png"
## [48] "modules"
## [49] "modules.zip"
## [50] "my first code.R"
## [51] "mycode.docx"
## [52] "mycode.html"
## [53] "mycode.R"
## [54] "myfirstRcode.R"
## [55] "New folder"
## [56] "New Folder (2)"
## [57] "New folder (3)"
## [58] "new1"
## [59] "newsave"
## [60] "newsave5"
## [61] "newsaved3.R"
## [62] "Quiz 1 R.docx"
## [63] "regressionR.html"
## [64] "regressionR.R"
## [65] "revisedR.html"
## [66] "revisedR.R"
## [67] "rfmanalysis2.html"
## [68] "rfmanalysis2.R"
## [69] "Rplot.png"
## [70] "rsconnect"
## [71] "Searches"
## [72] "Searches-20151024T142543Z.zip"
## [73] "SnowMap_Points.png"
## [74] "Takeout"
## [75] "takeout-20151024T142134Z.zip"
## [76] "Teaching"
## [77] "test.csv"
## [78] "Untitled (3).wma"
## [79] "Untitled (3).wma.wav"
## [80] "Untitled 88.wma"list.files("C:/Users/dell/Desktop/",pattern = "csv")## [1] "Analytics decisionstats.com Audience Overview 20110617-20120717.csv"
## [2] "BigDiamonds.csv"
## [3] "BigDiamonds.csv.zip"
## [4] "Boston.csv"
## [5] "ccFraud.csv"
## [6] "test.csv"myfirstfile=read.csv("C:/Users/dell/Desktop/Boston.csv" )
myfirstfile=read.csv("C:/Users/dell/Desktop/BigDiamonds.csv" )
memory.size()## [1] 110.52object.size(myfirstfile)## 59873760 bytesstr(myfirstfile)## 'data.frame': 598024 obs. of 13 variables:
## $ X : int 1 2 3 4 5 6 7 8 9 10 ...
## $ carat : num 0.25 0.23 0.34 0.21 0.31 0.2 0.2 0.22 0.23 0.2 ...
## $ cut : Factor w/ 3 levels "Good","Ideal",..: 3 1 1 3 3 1 1 3 3 1 ...
## $ color : Factor w/ 9 levels "D","E","F","G",..: 8 4 7 1 8 4 4 1 8 3 ...
## $ clarity : Factor w/ 9 levels "I1","I2","IF",..: 1 1 2 1 1 5 5 1 5 4 ...
## $ table : num 59 61 58 60 59 60 63 61 57.5 65 ...
## $ depth : num 63.7 58.1 58.7 60.6 62.2 64.4 62.6 59.2 63.6 54.9 ...
## $ cert : Factor w/ 9 levels "AGS","EGL","EGL Intl.",..: 6 6 6 6 2 6 6 6 8 6 ...
## $ measurements: Factor w/ 241453 levels ""," 3.99 x 3.95 x 2.44",..: 19960 21917 48457 15701 37341 14661 14400 19642 17115 16177 ...
## $ price : int NA NA NA NA NA NA NA NA NA NA ...
## $ x : num 3.96 4 4.56 3.8 4.35 3.74 3.72 3.95 3.87 3.83 ...
## $ y : num 3.95 4.05 4.53 3.82 4.26 3.67 3.65 3.97 3.9 4 ...
## $ z : num 2.52 2.3 2.67 2.31 2.68 2.38 2.31 2.34 2.47 2.14 ...#install.packages("data.table")
library(data.table)
newfile=fread("C:/Users/dell/Desktop/BigDiamonds.csv" )##
Read 23.4% of 598024 rows
Read 51.8% of 598024 rows
Read 80.3% of 598024 rows
Read 598024 rows and 13 (of 13) columns from 0.049 GB file in 00:00:05object.size(newfile)## 78044224 bytestables()## NAME NROW NCOL MB
## [1,] newfile 598,024 13 75
## COLS
## [1,] V1,carat,cut,color,clarity,table,depth,cert,measurements,price,x,y,z
## KEY
## [1,]
## Total: 75MB