gop<-matrix(gop)
ls()
## character(0)
rm(gop)
## Warning in rm(gop): 객체 'gop'를 찾을 수 없습니다
gop<-""
for( i in 1:9 )
{
for( j in 1:9 )
{
print(paste(i, "*", j, "=", i*j)) ;
multi <- paste(i, "*", j, "=", i*j) ;
gop <- c(gop, multi)
}
}
## [1] "1 * 1 = 1"
## [1] "1 * 2 = 2"
## [1] "1 * 3 = 3"
## [1] "1 * 4 = 4"
## [1] "1 * 5 = 5"
## [1] "1 * 6 = 6"
## [1] "1 * 7 = 7"
## [1] "1 * 8 = 8"
## [1] "1 * 9 = 9"
## [1] "2 * 1 = 2"
## [1] "2 * 2 = 4"
## [1] "2 * 3 = 6"
## [1] "2 * 4 = 8"
## [1] "2 * 5 = 10"
## [1] "2 * 6 = 12"
## [1] "2 * 7 = 14"
## [1] "2 * 8 = 16"
## [1] "2 * 9 = 18"
## [1] "3 * 1 = 3"
## [1] "3 * 2 = 6"
## [1] "3 * 3 = 9"
## [1] "3 * 4 = 12"
## [1] "3 * 5 = 15"
## [1] "3 * 6 = 18"
## [1] "3 * 7 = 21"
## [1] "3 * 8 = 24"
## [1] "3 * 9 = 27"
## [1] "4 * 1 = 4"
## [1] "4 * 2 = 8"
## [1] "4 * 3 = 12"
## [1] "4 * 4 = 16"
## [1] "4 * 5 = 20"
## [1] "4 * 6 = 24"
## [1] "4 * 7 = 28"
## [1] "4 * 8 = 32"
## [1] "4 * 9 = 36"
## [1] "5 * 1 = 5"
## [1] "5 * 2 = 10"
## [1] "5 * 3 = 15"
## [1] "5 * 4 = 20"
## [1] "5 * 5 = 25"
## [1] "5 * 6 = 30"
## [1] "5 * 7 = 35"
## [1] "5 * 8 = 40"
## [1] "5 * 9 = 45"
## [1] "6 * 1 = 6"
## [1] "6 * 2 = 12"
## [1] "6 * 3 = 18"
## [1] "6 * 4 = 24"
## [1] "6 * 5 = 30"
## [1] "6 * 6 = 36"
## [1] "6 * 7 = 42"
## [1] "6 * 8 = 48"
## [1] "6 * 9 = 54"
## [1] "7 * 1 = 7"
## [1] "7 * 2 = 14"
## [1] "7 * 3 = 21"
## [1] "7 * 4 = 28"
## [1] "7 * 5 = 35"
## [1] "7 * 6 = 42"
## [1] "7 * 7 = 49"
## [1] "7 * 8 = 56"
## [1] "7 * 9 = 63"
## [1] "8 * 1 = 8"
## [1] "8 * 2 = 16"
## [1] "8 * 3 = 24"
## [1] "8 * 4 = 32"
## [1] "8 * 5 = 40"
## [1] "8 * 6 = 48"
## [1] "8 * 7 = 56"
## [1] "8 * 8 = 64"
## [1] "8 * 9 = 72"
## [1] "9 * 1 = 9"
## [1] "9 * 2 = 18"
## [1] "9 * 3 = 27"
## [1] "9 * 4 = 36"
## [1] "9 * 5 = 45"
## [1] "9 * 6 = 54"
## [1] "9 * 7 = 63"
## [1] "9 * 8 = 72"
## [1] "9 * 9 = 81"
gop <- as.factor(gop)
gop
## [1] 1 * 1 = 1 1 * 2 = 2 1 * 3 = 3 1 * 4 = 4 1 * 5 = 5
## [7] 1 * 6 = 6 1 * 7 = 7 1 * 8 = 8 1 * 9 = 9 2 * 1 = 2 2 * 2 = 4
## [13] 2 * 3 = 6 2 * 4 = 8 2 * 5 = 10 2 * 6 = 12 2 * 7 = 14 2 * 8 = 16
## [19] 2 * 9 = 18 3 * 1 = 3 3 * 2 = 6 3 * 3 = 9 3 * 4 = 12 3 * 5 = 15
## [25] 3 * 6 = 18 3 * 7 = 21 3 * 8 = 24 3 * 9 = 27 4 * 1 = 4 4 * 2 = 8
## [31] 4 * 3 = 12 4 * 4 = 16 4 * 5 = 20 4 * 6 = 24 4 * 7 = 28 4 * 8 = 32
## [37] 4 * 9 = 36 5 * 1 = 5 5 * 2 = 10 5 * 3 = 15 5 * 4 = 20 5 * 5 = 25
## [43] 5 * 6 = 30 5 * 7 = 35 5 * 8 = 40 5 * 9 = 45 6 * 1 = 6 6 * 2 = 12
## [49] 6 * 3 = 18 6 * 4 = 24 6 * 5 = 30 6 * 6 = 36 6 * 7 = 42 6 * 8 = 48
## [55] 6 * 9 = 54 7 * 1 = 7 7 * 2 = 14 7 * 3 = 21 7 * 4 = 28 7 * 5 = 35
## [61] 7 * 6 = 42 7 * 7 = 49 7 * 8 = 56 7 * 9 = 63 8 * 1 = 8 8 * 2 = 16
## [67] 8 * 3 = 24 8 * 4 = 32 8 * 5 = 40 8 * 6 = 48 8 * 7 = 56 8 * 8 = 64
## [73] 8 * 9 = 72 9 * 1 = 9 9 * 2 = 18 9 * 3 = 27 9 * 4 = 36 9 * 5 = 45
## [79] 9 * 6 = 54 9 * 7 = 63 9 * 8 = 72 9 * 9 = 81
## 82 Levels: 1 * 1 = 1 1 * 2 = 2 1 * 3 = 3 1 * 4 = 4 ... 9 * 9 = 81
gopdel <-gop[c(2:82)]
gop1dan <-gopdel[c(1:9)]
#81개의 factor요소를 9행 9열의 행렬로 변환.............
gopmat <- matrix(gopdel, nrow=9, ncol=9)
gopmat[,1]
## [1] "1 * 1 = 1" "1 * 2 = 2" "1 * 3 = 3" "1 * 4 = 4" "1 * 5 = 5" "1 * 6 = 6"
## [7] "1 * 7 = 7" "1 * 8 = 8" "1 * 9 = 9"
#문자 연결 함수 paste의 인수 sep는 띄어쓰기 구분바 지정에 사용되는데,
#구분자 없이 붙여쓸때는 sep=""와 동일하며
#paste0() 함수로 구분자 없이 사용 가능하다.
#paste(x, "번째", sep=" ")
#paste0() : 아래와 같이 벡터 다중 반복 작업도 가능
paste0(1:12, c("st", "nd", "rd", rep("th", 9)))
## [1] "1st" "2nd" "3rd" "4th" "5th" "6th" "7th" "8th" "9th" "10th"
## [11] "11th" "12th"
# while(조건) 반복문
y <- c(1, 5)
x <- y/2
while (any(abs(x*x-y) > 1e-10))
{
x <- (x + y/x)/2
}
x
## [1] 1.000000 2.236068
x^2
## [1] 1 5
# repeat{expression; break}
y <- c(1, 5)
x <- y/2
repeat{
x <- (x + y/x)/2
if (any(abs(x*x-y) < 1e-10)) break
}
x
## [1] 1.000000 2.236068
x^2
## [1] 1 5
# for loops over a fixed set
x <- seq(0, 1, 0.01)
plot(x, x, ylab="y", type="l")
for (j in 1:20)
lines(x, x^j)
#tip <-과 =의 차
#The operators <- and = assign into the environment in which they are evaluated.
#The operator <- can be used anywhere, whereas the operator = is only allowed at the top level
#(e.g., in the complete expression typed at the command prompt) or as one of the subexpressions in a braced list of expressions.
#---------------------------------------------------------
#tip 실행시간 측정
ptm <- proc.time()
# 로직
x <- 1:100000
for (i in seq_along(x)) x[i] <- x[i]+1
proc.time() - ptm
## user system elapsed
## 0.19 0.00 0.18
#---------------------------------------------------------