Hantz_Angrand_week2_HW2

Upload file population of us named bigcity

getwd()

## [1] "C:/Users/hangr/Documents/SPSummer/RSummer"

uscity<-read.csv("bigcity.csv")
head(uscity)

summary of uscity dataset

summary(uscity)

##        X            u               x        
##  Min.   : 1   Min.   :  2.0   Min.   : 46.0  
##  1st Qu.:13   1st Qu.: 43.0   1st Qu.: 58.0  
##  Median :25   Median : 64.0   Median : 79.0  
##  Mean   :25   Mean   :103.1   Mean   :127.8  
##  3rd Qu.:37   3rd Qu.:120.0   3rd Qu.:130.0  
##  Max.   :49   Max.   :507.0   Max.   :634.0

Mean of two variables

mean(uscity$X)

## [1] 25

median(uscity$X)

## [1] 25

mean(uscity$u)

## [1] 103.1429

median(uscity$u)

## [1] 64

Create new data frame with with a subset of the columns and rows

uscity_sub<-uscity[,c('x','u')]
head(uscity_sub)

create new column name for the subset

colnames(uscity_sub)<-c("pop_1920","pop_1930")
head(uscity_sub)

Summary of new dataframe. Mean and median for the same two atrributes

summary(uscity_sub)

##     pop_1920        pop_1930    
##  Min.   : 46.0   Min.   :  2.0  
##  1st Qu.: 58.0   1st Qu.: 43.0  
##  Median : 79.0   Median : 64.0  
##  Mean   :127.8   Mean   :103.1  
##  3rd Qu.:130.0   3rd Qu.:120.0  
##  Max.   :634.0   Max.   :507.0

mean(uscity_sub$pop_1920)

## [1] 127.7959

median(uscity_sub$pop_1920)

## [1] 79

mean(uscity_sub$pop_1930)

## [1] 103.1429

median(uscity_sub$pop_1930)

## [1] 64

Forquestion 5 upload a new file and rename the columns

getwd()

## [1] "C:/Users/hangr/Documents/SPSummer/RSummer"

acme<-read.csv("acme.csv")

head(acme)

names(acme)<-gsub("e", "excellent", names(acme))
acme

Read from github

bigcity<-read.csv("https://github.com/HantzSPS/SPS/blob/master/bigcity.csv", sep = ",", na.strings = "NA", strip.white = TRUE, stringsAsFactors = FALSE)

## Warning in scan(file = file, what = what, sep = sep, quote = quote, dec =
## dec, : EOF within quoted string

library(dplyr)

## Warning: package 'dplyr' was built under R version 3.4.4

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

bigcitydf<-tbl_df(bigcity)

bigcitydf