On 10/25/2011 01:20 PM, Larry Evans wrote:
The page:
http://headmyshoulder.github.com/odeint-v2/doc/boost_sandbox_numeric_odeint/...
says:
The equations of motion are given by x'' = -x + γ x'. This can be transformed to a system of two coupled first-order differential equations with new variables x and p=x'. To apply numerical integration one first has to design the right hand side of the equation w' = f(w) where in this case w = (x,p):
which initially confused me because x was not a new variable as claimed by:
new variables x and p=x'
I think it would be clearer if it read:
with new variables w_1=x and w_2=x'.
and then:
w = (w_1,w_2)
which would emphasize that w was a vector and f was a function taking a vector and returning a vector.
Ok, you are right. It is pedagogical not very clever. I will change it. Btw. this method can always be applied to transform any higher-order ODE into a system of coupled first order ODEs. Best regards, Karsten
-regards, Larry
_______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users