Can any one help me?

how to solve this error?

??? Error: File: noise.m Line: 31 Column: 10
Unexpected MATLAB expression.

My mat lab code is

function x=signal(f,fs,N)
% sinusoid
 f=30;    %frequency, 
 N=20;    %number of samples
 fs=100;   %sampling frequency
 A=2;      %amplitute 
%Total sampling time = 1 second
n = 0:N-1; % numbering the samples
x = A*sin(2*pi*f*n/fs);
subplot(2,1,1);
plot(x)
title('Noise signal (x(n))')
axis([0,20,-2,2]);
ylabel('Amplitude');
xlabel('Discrete time n');
MFx = abs(fft(x));
frek=(0:N/2-1)*fs/N;
subplot(2,1,2)
plot(frek,MFx(1:N/2),'m')% plot the positive frequencies
title('FFT of Noise signal (x(n))');
axis([0 40 0 100]);
ylabel('Frequency');
xlabel('No. of Iteration');
k=10;
h=zeros(1,k);
h(3)=1;
h(4)=-2.7083;
h(5)=4.1861;
h(6)=-3.0451;
h(7)=0.73071;
d(n)=h(3)x(n-3)+h(4)x(n-4)+h(5)x(n-5)+h(6)x(n-6)+h(7)x(n-7);
ff_mix = abs(fft(d,1024));
subplot(2,2,1);
plot(d(n))
title('input: 1 primary signal (d(n))')
axis([0,20,-6,6]);
ylabel('Amplitude');
xlabel('Discrete time n');
subplot(2,2,2);
plot(ff_mix,'m');
title('FFT of primary signal (d(n))');
axis([0 1000 0 100]);
ylabel('Frequency');
xlabel('No. of Iteration');

Thank you very much

[Walter Roberson]

http://www.mathworks.co.uk/matlabcentral/answers/43073-a-guide-to-tags

Answer 1

[Walter Roberson]

Your line

d(n)=h(3)x(n-3)+h(4)x(n-4)+h(5)x(n-5)+h(6)x(n-6)+h(7)x(n-7);

has nothing between the h(3) and the x that follows it. You have the same problem several times on that line.