# 1 - pag. 567-568
tbl <- c(268,41,32,32,28,120,41,20,12,121)
tbl

ptbl <- prop.table(tbl)
# the same can be obtained with
ptbl <- tbl/sum(tbl)
ptbl

region <- c("Florida","Hawaii","California","Sud Carolina","Nord Carolina","Australia","Sud Africa","Brasile","Bahamas","Altri")

data.frame(Paesi= region,
           Frequenze = tbl,
           Proporzioni = round(ptbl,3),
           Percentuali = round(ptbl*100,1))


# ------------------------------------------
# Table 2.4 Frequency Table for Sodium in 20 Breakfast Cereals.

#data
x <- c(0,340,70,140,200,180,210,150,100,130,140,180,190,160,290,50,220,180,200,210)

# equal intervals (breaks)
brk <- c(0,40,80,120,160,200,240,280,320,360)

#classify obs. within intervals
xx <- cut(x,brk,right=FALSE)

#Count number of observations on each interval
tbl <- table(xx)

#create book’s Table 2.4
ptbl <- prop.table(tbl)

Tab2.4<- data.frame(
Intervalli=names(tbl),
Frequenze=as.numeric(tbl),
Proporzioni=round(as.numeric(ptbl),3),
Percentuali=round(as.numeric(ptbl)*100,1)
)

Tab2.4

barplot(tbl,# Frequency data
space = 0,# Space between bars
xlab="Sodium (mg)",# X axis label
ylab="Frequency")# Y axis label

# ------------------------------------------
# straightforward function
hist(x)

#use the built-in hist() function
hist(x,
breaks = c(0,39,79,119,159,199,239,279,319,359),
right = TRUE,
main = NULL,
xlab = "Sodium (mg)",
freq = TRUE,
xaxt = "n"# remove x-axis tickmarks
     )

#Put them back in the right place...
axis(side = 1,at = c(0,40,80,120,160,200,240,280,320,360))




# ------------------------------------------
#removing breaks


hist(x,
#breaks = c(0,39,79,119,159,199,239,279,319,359),
right = TRUE,
main = NULL,
xlab = "Sodium (mg)",
freq = TRUE,
#xaxt = "n"# remove x-axis tickmarks
     )


# ------------------------------------------
# setting freq = FALSE


#use the built-in hist() function
hist(x,
breaks = c(0,39,79,119,159,199,239,279,319,359),
right = TRUE,
main = NULL,
xlab = "Sodium (mg)",
freq = FALSE,
xaxt = "n"# remove x-axis tickmarks
     )

#Put them back in the right place...
axis(side = 1,at = c(0,40,80,120,160,200,240,280,320,360))

# ------------------------------------------
# density computation

#class amplitude
brk
diff(brk)

#class proportion
ptbl

# density = class relative frequency/class amplitude
density = ptbl/40
density

# ------------------------------------------
#Time Plots
#install package from local file (.zip or tar.gz)
# For Windows users
install.packages("C://Users//Grassi//Downloads//sasld_1.0.tar.gz",type = "source")
# For Mac a typical path could be: "~/../.../",
# install.packages("~/Downloads/sasld_1.0.tar",type = "source",repos = NULL) # important set repos=NULL; getOption("repos")


# 3 - pag. 569
#load ny data set
library(sasld)
data(ny)

plot(x = ny$YEAR,
y = ny$ANNUAL,
type = "l",
pch = 19,
xlab = "Anno",
ylab = "Temperatura Media Annuale"
)

lines(
lowess(ny$ANNUAL ~ ny$YEAR),
lwd=2)





# Change y limits
plot(x = ny$YEAR,
y = ny$ANNUAL,
type = "l",
pch = 19,
xlab = "Anno",
ylab = "Temperatura Media Annuale",
ylim = c(20,90))



#and add AUG - APR and FEB
points(ny$YEAR,ny$AUG,type="l",col="red")
points(ny$YEAR,ny$APR,type="l",col="orange")
points(ny$YEAR,ny$FEB,type="l",col="blue")

legend(x=1980,y=70,
legend=c("FEB","APR","AUG"),
text.col=c("blue","orange","red"))