octave:2> r = 2;
octave:3> odefun = @(t, y) r * y * (1 - y);
octave:4> dodefundy = @(t, y) r * (1-2*y);
octave:5> tspan = linspace (0, 1, 51);
octave:6> y0 = 2;
octave:7> [tout,yout]=euleroimplicito(odefun,tspan,y0,dodefundy);
octave:8> plot (tout, y0 * exp (r * tout) ./ (1 + y0 * (exp(r * tout) - 1)),tout,yout,'o')
octave:9> 
octave:9> 
octave:9> 
octave:9> VR123456
esercizio 1
Premere un tasto per continuare

octave:9> n=4
n =  4
octave:10> x=cos(((2*(1:n+1)-1)*pi)/(2*(n+1)))
x =

   9.5106e-01   5.8779e-01   6.1232e-17  -5.8779e-01  -9.5106e-01

octave:11> cos(pi/2)
ans =    6.1232e-17
octave:12> format long e
octave:13> x
x =

   9.510565162951535e-01   5.877852522924731e-01   6.123233995736766e-17  -5.877852522924730e-01  -9.510565162951535e-01

octave:14> y=sin(pi/2-((2*(1:n+1)-1)*pi)/(2*(n+1)))
y =

   9.510565162951535e-01   5.877852522924731e-01   0.000000000000000e+00  -5.877852522924731e-01  -9.510565162951535e-01

octave:15> ((2*(1:n+1)-1)*pi)/(2*(n+1))
ans =

   3.141592653589793e-01   9.424777960769379e-01   1.570796326794897e+00   2.199114857512855e+00   2.827433388230814e+00

octave:16> pi/2-((2*(1:n+1)-1)*pi)/(2*(n+1))
ans =

   1.256637061435917e+00   6.283185307179586e-01   0.000000000000000e+00  -6.283185307179586e-01  -1.256637061435917e+00

octave:17> sin(0)
ans =    0.000000000000000e+00
octave:18> cos(pi/2)
ans =    6.123233995736766e-17
octave:19> x=rand
x =    2.465439134797558e-02
octave:20> exp(-x)==1/exp(x)
ans = 1
octave:21> diary off