Bar-plot

# Data input

> x<-c(28,27,30,32,29,32,33,27,23,22,26,20)

> y<-c(29,37,34,37,29,28,33,36,33,32,26,31)

# Data output

> x

[1] 28 27 30 32 29 32 33 27 23 22 26 20

> y

[1] 29 37 34 37 29 28 33 36 33 32 26 31

# Calculate means

> mean(x)

[1] 27.41667

> mean(y)

[1] 32.08333

# Put x and y data into "Osaka" and "Tokyo", respectively

> Osaka<-mean(x)

> Tokyo<-mean(y)

# Make data column

> b<-c(Osaka, Tokyo)

# Bar-plot with names.

> barplot(b, names=c("Osaka", "Tokyo"))

# Calcurate SD

> sd(x)

[1] 4.144182

> sd(y)

[1] 3.604501

# Make SD column

sdxy<-c(sd(x), sd(y))

# Calculate max and minimum of bar

> (ci.l<-b+sdxy)

[1] 31.56085 35.68783

> (ci.u<-b-sdxy)

[1] 23.27248 28.47883

# Put error bar

# * gplots package is required to make a graph with error bar.

> install.packages("gplots")

# Open "gplots" pakage

> library(gplots)

# Draw graph with error bar (SD)

> barplot2(b, beside=TRUE, names=c("Osaka", "Tokyo"), ylim = c(0,40), plot.ci=TRUE, ci.l=ci.l, ci.u=ci.u, plot.grid=TRUE)

# Calcurate SE

> sex=sd(x)/sqrt(length(x))

> sey=sd(y)/sqrt(length(y))

# SE output

> sex

[1] 1.196322

> sey

[1] 1.040530

# Make SE column

sexy<-c(sex, sey)

# Confirm SE column

> sexy

[1] 1.196322 1.040530

# Calculate max and minimum of bar (SE)

> (ci.l<-b+sexy)

[1] 28.61299 33.12386

> (ci.u<-b-sexy)

[1] 26.22034 31.04280

# Open "gplots" pakage

> library(gplots)

# Draw graph with error bar (SD)

> barplot2(b, beside=TRUE, names=c("Osaka", "Tokyo"), ylim = c(0,40), plot.ci=TRUE, ci.l=ci.l, ci.u=ci.u, plot.grid=TRUE)