i want to filter a frequeny

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Hi all,

I write because I'm trying to do filtering in maltab.

in the code below I have a signal which is composed of two sinus of frequencies 0.3Hz and 2Hz.

I'd like to do is filter the sinus 2Hz the code below does not kidnapped this signal's component ...

you know where it comes from?

clear all;close all;clc;
%%original
t = 0:0.01:10;
y = sin(2*pi*0.3*t)+sin(2*pi*2*t);
%%filter
fs = 1000;
fcoupure = 2*[1 3]/fs;
[b]=fir1(1,fcoupure,'stop');
yfilter=filter(b,1,y);
figure (1);hold on;plot(t,y);plot(t,yfilter,'r');
%%butterworth
fs = 1000;
fcoupure = 2*[1 3]/fs;
[b,a]=butter(1,fcoupure,'stop');
yfilter=filter(b,a,y);
figure (2);hold on;plot(t,y);plot(t,yfilter,'r');