머신러닝과 빅데이터 분석

 

(3주차 수업. 데이터 분석 실습) 

-데이터 타입 : 벡터, 행렬, 배열, 리스트, 데이터프레임 

 

 

변수명 <-c ()

x<-c(1,2,3) 

 

mode()

str() 

length() 

typeof() 

 

remove()

rm()

factor(데이터, labels=c("A", "B", "O", "AB"))

matrix(c(1,2,3,4,5,6),nrow=2,ncol=4) 

array(c(1,2,3,4,5,6,7,8,9,10,11,12), dim=c(2,3,2))

x5<-list(1,"hello",c(10,20,30))

str(x5)

 

 

id<-c(101,102,103)

gender<-c('f',''m',f')

addr<-('서울','부산','광주')

df<-data.frame(id,gender,addr)

df

str(df)

 

 

 

id<-c(1,2,3)

gender<-c('f','m','m')

df<-data.frame(id=id, gender=gender)

df

View(df)

str(df)

read.table("test_data.txt", header=TRUE)

read.table("C:/aaaa/bbb/test_data.txt", header=TRUE)

 

read.table("test_data_col.txt")

read.table("test_data_col.txt",col.names=c('id','gender,'age','addr'))

 

read.table("test_data.txt", header=TRUE, skip = 2) 

read.table("test_data.txt",header=TRUE,nrows=5)

read.table("test_Data2.txt", sep=",", header=TRUE)

read.csv("test_data.csv")

 

install.packages("readxl")

library(readxl)

read_excel("test_data.xlsx") 

 

install.packages("XML")

library(XML)

xmlToDataFrame("test_data.xml")

 

install.packages("jsonlite")

library(jsonlite)

fromJSON("test_data.json")

 

str(iris)

ncol(iris)

nrow(iris)

dim(iris)

ls(iris)

head(iris)

tail(iris)

head(iris,n=20)

mean(iris$Sepal.Length)

median(iris$Sepal.Length)

range(iris$Sepal.Length)

 

quantile(iris$Sepal.Length)

quantile(iris$Sepal.Length, probs=0.8)

var(iris$Sepal.Length)

sd(iris$Sepal.Length)