計算機数学の答え。　こっちのほうが正しいはず.

以下本文。

real dy1,dy2,dy3,dy4,dz1,dz2,dz3,dz4,x,y

real x0,xend,dx,f,z

read (5,*) x0,y0,z0,xend,dx

xend = xend + dx/2.0

do 100 x=x0,xend,dx

write (6,1) x,y,0.0000001*z

1 format(‘ ‘,5f10.8)

dy1=dx*(z)

dy2=dx*(z+dy1/2)

dy3=dx*(z+dy2/2)

dy4=dx*(z+dy3)

y=y+(dy1+2*dy2+2*dy3+dy4)/6

dz1=dx*f(y,z)

dz2=dx*f(y,z+dz1/2)

dz3=dx*f(y,z+dz2/2)

dz4=dx*f(y,z+dz3)

z=z+(dz1+2*dz2+2*dz3+dz4)/6

100 continue

stop

end

real function f(x,y)

real x,y

f=(100000-100000*x-2*y)*100000

return

end