From: Minimax on
Hello!
I have 3d series of z500[lat,lon,t],
where

lat=1:63 (latitude)
lon=1:144 (longitude)
t=1:1464 (time with 6 hours timestep)
1 day==4 timesteps

And I want to do a bandpass filter from 1 to 5 days.
I use the code:

[b,a] = butter(1,[ 1/(5*4) 1/(1*4) ],'stop');
y=filter(b,a,z500);

Is this correct code?