R Homework 2_Mengqin Cai
Mengqin Cai
7/27/2019
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#1.Use the summary function to gain an overview of the data set. Then display the mean and median.
theUrl<-"https://raw.github.com/vincentarelbundock/Rdatasets/master/csv/boot/poisons.csv"
Animal<-read.table(file=theUrl, header=TRUE, sep=",")
Animal## X time poison treat
## 1 1 0.31 1 A
## 2 2 0.45 1 A
## 3 3 0.46 1 A
## 4 4 0.43 1 A
## 5 5 0.36 2 A
## 6 6 0.29 2 A
## 7 7 0.40 2 A
## 8 8 0.23 2 A
## 9 9 0.22 3 A
## 10 10 0.21 3 A
## 11 11 0.18 3 A
## 12 12 0.23 3 A
## 13 13 0.82 1 B
## 14 14 1.10 1 B
## 15 15 0.88 1 B
## 16 16 0.72 1 B
## 17 17 0.92 2 B
## 18 18 0.61 2 B
## 19 19 0.49 2 B
## 20 20 1.24 2 B
## 21 21 0.30 3 B
## 22 22 0.37 3 B
## 23 23 0.38 3 B
## 24 24 0.29 3 B
## 25 25 0.43 1 C
## 26 26 0.45 1 C
## 27 27 0.63 1 C
## 28 28 0.76 1 C
## 29 29 0.44 2 C
## 30 30 0.35 2 C
## 31 31 0.31 2 C
## 32 32 0.40 2 C
## 33 33 0.23 3 C
## 34 34 0.25 3 C
## 35 35 0.24 3 C
## 36 36 0.22 3 C
## 37 37 0.45 1 D
## 38 38 0.71 1 D
## 39 39 0.66 1 D
## 40 40 0.62 1 D
## 41 41 0.56 2 D
## 42 42 1.02 2 D
## 43 43 0.71 2 D
## 44 44 0.38 2 D
## 45 45 0.30 3 D
## 46 46 0.36 3 D
## 47 47 0.31 3 D
## 48 48 0.33 3 Dsummary(Animal)## X time poison treat
## Min. : 1.00 Min. :0.1800 Min. :1 A:12
## 1st Qu.:12.75 1st Qu.:0.3000 1st Qu.:1 B:12
## Median :24.50 Median :0.4000 Median :2 C:12
## Mean :24.50 Mean :0.4794 Mean :2 D:12
## 3rd Qu.:36.25 3rd Qu.:0.6225 3rd Qu.:3
## Max. :48.00 Max. :1.2400 Max. :3#2.subset of the columns and rows. Make sure to rename it
Animal2<-subset(Animal,poison>=2 & treat=="D")
Animal2## X time poison treat
## 41 41 0.56 2 D
## 42 42 1.02 2 D
## 43 43 0.71 2 D
## 44 44 0.38 2 D
## 45 45 0.30 3 D
## 46 46 0.36 3 D
## 47 47 0.31 3 D
## 48 48 0.33 3 D#3.Create new column names for the new data frame
colnames(Animal2)<-c("Number","TestTime","PoisonNumber","Treat")
Animal2## Number TestTime PoisonNumber Treat
## 41 41 0.56 2 D
## 42 42 1.02 2 D
## 43 43 0.71 2 D
## 44 44 0.38 2 D
## 45 45 0.30 3 D
## 46 46 0.36 3 D
## 47 47 0.31 3 D
## 48 48 0.33 3 D#4.Use the summary function to create an overview of your new data frame.Please compare
summary(Animal2)## Number TestTime PoisonNumber Treat
## Min. :41.00 Min. :0.3000 Min. :2.0 A:0
## 1st Qu.:42.75 1st Qu.:0.3250 1st Qu.:2.0 B:0
## Median :44.50 Median :0.3700 Median :2.5 C:0
## Mean :44.50 Mean :0.4963 Mean :2.5 D:8
## 3rd Qu.:46.25 3rd Qu.:0.5975 3rd Qu.:3.0
## Max. :48.00 Max. :1.0200 Max. :3.0#5.For at least 3 values in a column please rename so that every value in that column is renamed.
Animal3<-as.data.frame(sapply(Animal,gsub,pattern="A",replacement="Special",ignore.case = TRUE))
print(Animal3)## X time poison treat
## 1 1 0.31 1 Special
## 2 2 0.45 1 Special
## 3 3 0.46 1 Special
## 4 4 0.43 1 Special
## 5 5 0.36 2 Special
## 6 6 0.29 2 Special
## 7 7 0.4 2 Special
## 8 8 0.23 2 Special
## 9 9 0.22 3 Special
## 10 10 0.21 3 Special
## 11 11 0.18 3 Special
## 12 12 0.23 3 Special
## 13 13 0.82 1 B
## 14 14 1.1 1 B
## 15 15 0.88 1 B
## 16 16 0.72 1 B
## 17 17 0.92 2 B
## 18 18 0.61 2 B
## 19 19 0.49 2 B
## 20 20 1.24 2 B
## 21 21 0.3 3 B
## 22 22 0.37 3 B
## 23 23 0.38 3 B
## 24 24 0.29 3 B
## 25 25 0.43 1 C
## 26 26 0.45 1 C
## 27 27 0.63 1 C
## 28 28 0.76 1 C
## 29 29 0.44 2 C
## 30 30 0.35 2 C
## 31 31 0.31 2 C
## 32 32 0.4 2 C
## 33 33 0.23 3 C
## 34 34 0.25 3 C
## 35 35 0.24 3 C
## 36 36 0.22 3 C
## 37 37 0.45 1 D
## 38 38 0.71 1 D
## 39 39 0.66 1 D
## 40 40 0.62 1 D
## 41 41 0.56 2 D
## 42 42 1.02 2 D
## 43 43 0.71 2 D
## 44 44 0.38 2 D
## 45 45 0.3 3 D
## 46 46 0.36 3 D
## 47 47 0.31 3 D
## 48 48 0.33 3 D#6.Display enough rows to see examples of all of steps 1-5 above
head(Animal3,15)## X time poison treat
## 1 1 0.31 1 Special
## 2 2 0.45 1 Special
## 3 3 0.46 1 Special
## 4 4 0.43 1 Special
## 5 5 0.36 2 Special
## 6 6 0.29 2 Special
## 7 7 0.4 2 Special
## 8 8 0.23 2 Special
## 9 9 0.22 3 Special
## 10 10 0.21 3 Special
## 11 11 0.18 3 Special
## 12 12 0.23 3 Special
## 13 13 0.82 1 B
## 14 14 1.1 1 B
## 15 15 0.88 1 B tail(Animal3)## X time poison treat
## 43 43 0.71 2 D
## 44 44 0.38 2 D
## 45 45 0.3 3 D
## 46 46 0.36 3 D
## 47 47 0.31 3 D
## 48 48 0.33 3 DIncluding Plots
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