f <- function(x){
sin(x)-1/2
}
d<-1e-15
xl<-0
xr<-pi/2
xm<-(xl+xr)/2
while(abs(f(xm))>d){
if(f(xl)*f(xm)>0){
xl<-xm
}else if(f(xl)*f(xm)<0){
xr<-xm
}
xm<-(xl+xr)/2
}
print(xm)
f <- function(x){
sin(x)-1/2
}
f1<-function(x){
cos(x)
}
d<-1e-15
xold<-runif(1,0,pi/2)
xnew<-xold-f(xold)/f1(xold)
while(abs(xnew-xold)>d){
xold<-xnew
xnew<-xold-f(xold)/f1(xold)
}
print(xnew)*6
- LU分解
- 分解のみ
- 天下り的な書き方なので内容にそった書き方を考える
N<-3
M<-matrix(runif(N^2),N,N)
L<-U<-matrix(0,N,N)
A<-M
for(k in 1:(N-1)){
u <- A[k,k]
for(i in (k+1):N){
A[i,k] <- A[i,k]/u
t <- A[i,k]
L[i,k]<-t
for( j in (k+1):N){
A[i,j]<- A[i,j] -t*A[k,j]
}
}
}
U<-A-L
diag(L)<-1
M-L%*%U