Budownictwo 2006 Wydział Inżynierii Lądowej Politechniki Krakowskiej

barg

function[y]=f(x)
y=2*x*x*x-3*x*x+5*x -6;
end

function[y]=fp(x)
y=2*3*x*x-3*2*x+5;
end

function[x1,iter]=m_zmod_newt(a,b,eps)
fb=f(b);
fa=f(a);
fp=fp(b);

if fa*fb>0
break
end

x0=b;
for iter=1:150
x1=x0-f(x0)/fp;
if (abs(x1-x0)<eps)||(abs(f(x1))<1.e-10)
return
end
x0=x1;
end
end

a=-5;
b=10;
k=50;

d=(abs(a)+abs(b))/k;

xa=0;
for i=1:k+1
x(i)=a+xa;
y(i)=f(x(i));
xa=xa+d;
end

x_0=m_zmod_newt(a,b,0.001);
x_0

plot(x,y,"-",x_0,f(x_0),"*")
hold on
pause

Zenek Obornik

function[y]=f(x)

y=6*(x-4)*(x+3)*(x-9)

end

function[x,iter]=m_regfalsi(a,b,eps)

fa=f(a);

fb=f(b);

if fa*fb>0
break
end

for iter=1:150

x=a-fa/(fb-a)*(b-a);
fx=f(x);
if fa*fx>0

if(abs(x-a)<eps)||(abs(fx)<1.e-10)

return;

end

a=x;
fa=fx;

else

if(abs(x-b<eps))||(abs(fx)<1.e-10)

return;

end
b-x;
fb=fx;
end
end
end
c=-15
d=15
e=0.01
[c,d]=m_regfalsi(-15,15,0.01)

plot(x,y,"-@")
hold on
pause

Zenek Obornik

function[y]=f(x)

y=6*(x-4)*(x+3)*(x-9)

end

function[x,iter]=m_regfalsi(a,b,eps)

fa=f(a);

fb=f(b);

if fa*fb>0
break
end

for iter=1:150

x=a-fa/(fb-a)*(b-a);
fx=f(x);
if fa*fx>0

if(abs(x-a)<eps)||(abs(fx)<1.e-10)

return;

end

a=x;
fa=fx;

else

if(abs(x-b<eps))||(abs(fx)<1.e-10)

return;

end
b-x;
fb=fx;
end
end
end

a=-5;
b=10;
k=50;

Zenek Obornik

function[y]=f(x)

y=6*(x-4)*(x+3)*(x-9)

end

function[x,iter]=m_regfalsi(a,b,eps)

fa=f(a);

fb=f(b);

if fa*fb>0
break
end

for iter=1:150

x=a-fa/(fb-a)*(b-a);
fx=f(x);
if fa*fx>0

if(abs(x-a)<eps)||(abs(fx)<1.e-10)

return;

end

a=x;
fa=fx;

else

if(abs(x-b<eps))||(abs(fx)<1.e-10)

return;

end
b-x;
fb=fx;
end
end
end

a=-5;
b=10;
k=50;

d=(abs(a)+abs(b))/k;
[x0,iter]=m_regfalsi(-5,10,0.01)

xa=0;
for i=1:k+1

x(i)=a+xa;
y(i)=f(x(i));
xa=xa+d;
end

x0=m_regfalsi(a,b,0.01)
x0

plot(x,y,"-",x0,f(x0),"*")
hold on
pause