function [dxdt]=lorenz95_dxdt(t,x);
%% 
%    UMD AOSC 615   SPRING 2009
%   dxdt for Lorenz '63 systems 

%% global
% ode_prmtr=F
global ode_prmtr

%% setup
N=length(x); Np1=N+1; Np3=N+3;
xpad= [ x(N-1); x(N); x; x(1) ]; % deal w/ periodic BCs w/o if tests
F=ode_prmtr(1);

%% dxdt
dxdt= (xpad(4:Np3) -xpad(1:N)).*xpad(2:Np1) -x +F;

return
