Minimax
Posts:
12
Registered:
1/23/09


Re: How to make this bandpass filter?
Posted:
Jan 31, 2010 8:25 AM


"Wayne King" <wmkingty@gmail.com> wrote in message <hk3tui$mf6$1@fred.mathworks.com>... > "Minimax " <aseid@mail.ru> wrote in message <hk3j5m$j0k$1@fred.mathworks.com>... > > Good day! > > I have the 3d matrix z500(latitude,longitude,time), > > where > > latitue=1:73 > > longitude=1:144 > > time=1:124 (here 31 days, because 4 timestep is 1 day) > > > > I need a bandpass filter that passes days from 1 to 5. > > > > How to make this bandpass filter? > Hi, what makes you think you need a "bandpass filter" for this problem. Can you be more specific about what you're doing? To understand, you have a 73X144X124 matrix and you just want to extract the data corresponding to days 1 to 5? If that is the case and your data is Z, why can't you just do: > > NewData = Z(:,:,1:20); > > Wayne
Thank you for your help! Yes, i have a 73X144X124 matrix and i want to apply for my data a bandpass filter like below, but someone said that this code was incorrect. i need it for get the filtered field of Z with periods (1<=T<=5 days).
[b,a] = butter(1,[ 1/(5*4) 1/(1*4) ],'stop'); y=filter(b,a,z500);

