When you write `(...)^1/8`, you probably mean `(...)^(1/8)` instead. -erik
On Fri, Jun 10, 2016 at 10:29 PM, <[email protected]> wrote: > this is the test for equation differential using runge-kutta45: f(x,y)= > (-5*x - y/5)^1/8 + 10 > > > <https://lh3.googleusercontent.com/-D6U4d5pN0pw/V1t3MaV3JpI/AAAAAAAAACU/-E_ceVhrTxkT3SAgmLUy5nHDhRJTIikSgCLcB/s1600/rk45.png> > > why the numerical result is different? I used : > > function Rk_JL() > f(x,y)= (-5*x - y/5)^1/8 + 10 > tspan = 0:0.001:n > y0 = [0.0, 1.0] > return ODE.ode45(f, y0,tspan);end > > > and > > > function [X1,Y1] = RK_M() > f = @(x,y) (-5*x - y/5)^1/8 + 10; > tspan = 0:0.001:n; > y0 = 1 > [X1,Y1]= ode45(f,tspan,1);end > > -- Erik Schnetter <[email protected]> http://www.perimeterinstitute.ca/personal/eschnetter/
