部分响应中参数输入求大神解答请问fftseq应该输入什么值

Question

#matlab

请问fftseq应该输入什么值

```function [M,m,df]=fftseq(m,tz,df)
fz=1/tz;
if nargin==2   
n1=0;
else n1=fz/df;  
end  
n2=length(m);
n=2^(max(nextpow2(n1),nextpow2(n2)));
M=fft(m,n);     
m=[m,zeros(1,n-n2)];df=fz/n;

clear;
clear;
N=10;                   
fc=20;                  
datat=0.01;            
df=0.01                  
t=0:datat:N;            
m=randint(1,N);        
fs=1/datat;
c=cos(2*pi*fc*t); 
for i=1:length(m)
    if(m(i)==1)
        for j=1:1/datat;
            ask_pre(j+(i-1)*(1/datat))=1;
        end
    elseif(m(i==0))
            ask_pre(j+(i-1)*(1/datat))=0;
    end
end
ask_pre=[ask_pre,m(i)];
ask=ask_pre.*c;
[ask_F,ask,df1]=fftseq(ask,datat,df);
[C,c,df1]=fftseq(c,datat,df);
[M,ask_pre,df1]=fftseq(ask_pre,datat,df);
f=[0:df1:df1*(length(c)-1)]-fs/2;
subplot(3,1,1);plot(f,abs(fftshift(M)));xlabel('频率');  title('基带信号的频谱');
subplot(3,1,2);plot(f,abs(fftshift(C)));xlabel('频率');  title('载波信号的频谱');
subplot(3,1,3);plot(f,abs(fftshift(ask_F)));xlabel('频率');  title('2ask的频谱');