# 030 SUMMARY & DISPLAY OF DATA

#LOAD DATA:
Iris=read.table("iris.txt")
Iris=iris
#DESCRIPTIVE STATISTICS:
summary(Iris)
I=Iris[,1:4]
I

quantile(I$Sepal.Length,probs=seq(0,1,0.1))
variances=diag(var(I))
variances
sd=sqrt(variances)
sd
coefvar=sd/colMeans(I)
coefvar

#SCATTER PLOTS:
plot(Iris)

plot(Iris$Sepal.Length,Iris$Sepal.Width,col='red',pch=19)

plot(Iris$Sepal.Length,Iris$Sepal.Width,pch=19)
points(Iris$Sepal.Length[Iris$Species=='setosa'],Iris$Sepal.Width[Iris$Species=='setosa'],col='red',pch=19)
points(Iris$Sepal.Length[Iris$Species=='versicolor'],Iris$Sepal.Width[Iris$Species=='versicolor'],col='blue',pch=19)


#BOX PLOTS:
plot(Iris$Species,Iris$Sepal.Length)

library(lattice)
boxplot(Iris)

#HISTOGRAMS:
op=par(mfrow=c(2, 2))
hist(Iris$Sepal.Length,col='red')
hist(Iris$Sepal.Width,col='blue')
hist(Iris$Petal.Length,col='green')
hist(Iris$Petal.Width,col='purple')
par(op)


histogram(~ Sepal.Length | Species,data=Iris)
histogram(~ Sepal.Width | Species,data=Iris)
histogram(~ Petal.Length | Species,data=Iris)
histogram(~ Petal.Width | Species,data=Iris)