Jan30-Problems17-27

a<-list(aa=1,bb=2,cc=3) a

max(sample(1:100,30)) ? sample()

rnorm(10)

set.seed(5) random<-rnorm(10, mean=50,sd=10) random

se<-function(x){ v<-var(x) n<-length(x) return(sqrt(v/n)) }

mySample<-rnorm(100, mean=20,sd=4) mySample

se(mySample)

temp<-function(f){ celsius<-(5/9)*(f-32) return(celsius) }

vector<-c(12,67,78,100) vector temp(vector)

x<-rnorm(100) y<-rnorm(100) plot(x,y) plot(x,y, xlab= “This is the x axis”, ylab=“This is the y axis”, main=“Plot of X vs Y”)

g<-c(“f”,“f”,“m”,“f”,“m”) sex<-factor(g,levels=c(“f”,“m”)) sex h<-c(“adult”,“juvenile”,“adult”,“juvenile”,“adult”) age<-factor(h,levels=c(“adult”,“juvenile”)) t<-table(g,h) t margin.table(t,1)

site<-c(“A”,“B”,“A”,“A”,“B”) season<-c(“Winter”,“Summer”,“Summer”,“Spring”,“Fall”) pH<-c(7.4,6.3,8.66,7.2,8.9) df<-data.frame(site,season,pH) df df[3,2]

pH>7 pH[pH>7]

df[site==“A”,“pH”]

df[season==“Summer”,c(“site”,“pH”)]

df$NO3<-c(234.5,256.6,654.1,356.7,776.4) df

dim(df)