ch 2 exercise 3

### Ch 2 Exercise 3 ###########################

#Step 2 (set working directory)
getwd()

#Step 3 (import data)
ch2_iris_data <- read.csv("C:/Users/benny/Downloads/ch2_iris_data.csv")
View(ch2_iris_data)
mydf=ch2_iris_data

#Step 4 (first scatterplot - add code here when you get to Step 6) petal width v length
par(mfrow=c(1,2))
plot(mydf$Petal_Length_mm~mydf$Petal_Width_mm,col=mydf$Species_num,xlab="Petal width (mm)",ylab = "Petal length (mm)") #i titled this scatterplot but it overlapped with the title of both plots so i deleted it
plot(mydf$Sepal_Length_mm~mydf$Sepal_Width_mm,col=mydf$Species_num,xlab="Sepal width (mm)",ylab = "Sepal length (mm)")
title("Scatterplots of Petal and Sepal length and width",line = -2,outer = TRUE)

plot(Petal_Length_mm~Petal_Width_mm,data = mydf,col=mydf$Species_num,main="Scatterplot of Petal width v. length",xlab="Petal width (mm)",ylab = "Petal length (mm)")
abline(lm(Petal_Length_mm~Petal_Width_mm,data = mydf[which(mydf$Species_num==1),]))
abline(lm(Petal_Length_mm~Petal_Width_mm,data = mydf[which(mydf$Species_num==2),]),col="green")
abline(lm(Petal_Length_mm~Petal_Width_mm,data = mydf[which(mydf$Species_num==3),]),col="red") #great success in copy-pasting my code from the sepal plot and editing it to make this code


#Step 4 (second scatterplot) sepal width v length
plot(Sepal_Length_mm~Sepal_Width_mm,data = mydf,col=mydf$Species_num,main="Scatterplot of Sepal width v. length",xlab="Sepal width (mm)",ylab = "Sepal length (mm)") #code that makes plot
abline(lm(Sepal_Length_mm~Sepal_Width_mm,data = mydf[which(mydf$Species_num==1),])) #makes line of regression for first species
abline(lm(Sepal_Length_mm~Sepal_Width_mm,data = mydf[which(mydf$Species_num==2),]),col="green") #so cool seeing "green" light up that color
abline(lm(Sepal_Length_mm~Sepal_Width_mm,data = mydf[which(mydf$Species_num==3),]),col="red")

#Step 5 (add legend to the second scatterplot)
legend("topleft",legend = c("I. setosa","I. versicolor","I. verginica"),col = c("black","green","red"),pch = 1,lty = 1)

#Step 7 (create a new data frame)
  #iris_data$Petal_Length_mm #prints a single column in a df //petal then species
x=c(mydf$Petal_Width_mm)
y=c(mydf$Species_name)
pw_df=data.frame(x,y)

#Step 8 (unstack)
unstack_df=unstack(pw_df)

#Step 9 (output data frame as .csv)
write.csv(pw_df,file = "unstacked")