# illustration for ensemble kalman filter for the presentation.
graphics.off()
x11(width=11.25,height=7.8)
library( fields)    # load fields package (available at CRAN)
source( 'L96.example.r')


# Lorenz 96 system steped at .02 time step nearly linear between steps of 
# these sizes.
anim1(N=100)

# Lorenz 96 system stepped at .1 time step showing divergence of initial 
#conditions. 
anim2(N=20,MM=15, dt=.1)

# step through 20 time points and every fifth time generate data and 
# assimilate 
# number of ensemble members is 15 observation error variance 
# is .5**2 every other location is observed. 
EKF(N=20,MM=15,dt=.1)

# if we only take 2 ensemble members we observe filter divergence.
EKF(N=20,MM=2,dt=.1,tempo=F)


# reinhard furrer, april, 20th 2004, based on functions by doug nychka