help.start()
help.search(plot)
help.search("plot")
?plot
2+3
a <- 2+3
a
2^3 -> b
b
c <- b
b <- 6
b
c
3.14 -> d
d
Inf
NaN
5/0
Inf-Inf
2+3i
"ABC"
TRUE
T
FALSE
F
t
TRUE & FALSE
TRUE | FALSE
all(T,T,F)
any(T,T,F)
a == b
a > 2
a >= 2
a
a %% 2
a %/% 2
a
mode(a)
s <- "abc"
mode(s)
L <- T
mode(L)
NAű
NA
NULL
is.numeric(a)
is.numeric(s)
as.numeric("123")
as.character(3.14)
f <- c(3,0,-2.5)
f
g <- c(2, "abc")
g
1:5
5:1
seq(1,5)
seq(1,5,2)
seq(1,5,length=10)
seq(1,by=2,length=10)
seq(by=2,length=10,to=4)
?seq
?distributions
rnorm(10)
v <- 2:4
w <- c(3,0,-2)
v; w
v + w
2 * v
v * w
v ^w
x <- c(2,-2)
v
x + v
y <- 1:6
y + x
y
x
x[1]
x[0]
y[-1]
y
y[8]
y[c(1,3,4)]
y
y[c(1,3,4]
y[2:4]
y[-2:4]
y[-(2:4)]
2:4*2
y[c(1,3,1,3)]
y[c(1,3,1,3,1,3,1,3,1,3)]
x
y
L <- c(T,T,F,F,F,T)
y[L]
y[c(T,F)]
y > 2
y[y>2]
y[(y>2)&(y %% 2 == 1)]
A <- y
A
dim(A)
dim(A) <- c(2,3)
A
B <- matrix(-3:2,2,3)
B
C <- matrix(-3:2,2,3,byrow=TRUE)
C
C[1,2]
C[1,]
C[,2]
C[1,1:2]
C[-1,-2]
C[2]
C
C[6]
C[2,]
D <- matrix(1:4,2,2)
D
t(A)
A
t(A) %*% D
v
A %*% v
v %*% t(A)
w
v %*% w
crossprod(v,w)
outer(v,w)
det(D)
x
solve(D,x)
solve(D)
solve(D) %*% D
F <- matrix(c(1,2,1,2),2,2)
F
det(F)
solve(F)
A
lista <- list("abc", 23, TRUE)
lista
lista[4] <- x
lista[[4]] <- x
lista
names(lista)
names(lista) <- c(str,num,logical,vekt)
names(lista) <- c("str","num","logical","vekt")
lista
names(lista)[3] <- NA
lista
names(lista)[3] <- NULL
lista
lista[2]
lista[[2]]
lista$num
lista$vekt[2]
lista$vekt
lista[4]
lista[4][2]
lista[[4]][2]
data()
iris
?iris
head(iris)
edit(iris)
iris[2,3]
iris[2]
iris[2,]
iris$Species
mode(iris$Species)
class(iris$Species)
names(iris)
row.names(iris)
mode(iris$Sepal.Width)
iris[2:5,c(1,3,5)]
iris2 <- iris[5:10,]
iris2
iris2[2,]
iris2["6",]
x <- rnorm(10)
y <- rnorm(10)
runif[10]
runif(10)
round(1 + runif(10))
.Last.value
.Last.value -> halmaz
pontok <- data.frame(xkoord = x, ykoord = y, halmaz = halmaz)
pontok
pontok[1]
pontok$xkoord
pontok$tav <- sqrt(pontok$xkoord^2+pontok$ykoord^2)
pontok
class(pontok$halmaz)
pontok$halmaz <- factor(pontok$halmaz)
class(pontok$halmaz)
pontok$halmaz
halmaz
class(halmaz)
plot(halmaz)
plot(pontok$halmaz)
mean(pontok$tav)
length(pontok$tav)
sum(pontok$tav)
tapply(pontok$tav,pontok$halmaz,mean)
ls()
rm(A,B,g,f,F)
ls()
pontok$koord
pontok$xkoord
attach(pontok)
xkoord
plot(xkoord,ykoord)
pontok
xkoord <- rnorm(10) + 2
xkoord
pontok$xkoord
ls()
ykoord
detach(pontok)
ykoord
pontok$ykoord
attach(pontok)
xkoord
pontok$xkoord
detach(pontok)
rm(xkoord,halmaz)
attach(pontok)
plot(xkoord,ykoord)
plot(xkoord,ykoord,col="red")
?colors
colors()
plot(xkoord,ykoord,col=3)
plot(1:12,1:12,col=1:12)
plot(xkoord,ykoord,col=halmaz)
plot(xkoord,ykoord,pch="+")
plot(xkoord,ykoord,pch=4)
plot(1:12,1:12,pch=1:12)
plot(xkoord,ykoord,pch=halmaz)
plot(xkoord,ykoord,pch=halmaz+2)
plot(xkoord,ykoord,pch=as.numeric(halmaz))
plot(xkoord,ykoord,pch=as.numeric(halmaz),col=halmaz)
pontok
pontok[12,] <- list(rnorm(1),rnorm(1),2)
pontok
pontok[14,] <- 1
pontok
pontok[6] <- pontok$xkoord
x <- 3
y <- 4
x+y