how to remove error in this code?

%%K=10%%
a = 1000;
a = rand([-1 1],a,1);
b= (a >= 0);
bm=(a<0);
b1(b)=1;
b1(bm)=-1;
d=b1(:);
h=[1 0.25 -0.5];
c=conv(h,d);
e=c(1:end-2,:);
noise1 =normrnd(0,0.1,[length(e)],1); % noise signal of zero mean and 0.1 variance
f1= e+noise1;
t=f1(1:end-990,:); %take 10 values 
ss = 16; % NLMS step size
offset = 50; % NLMS offset
ha = adaptfilt.nlms(3,ss,1,offset);
stem([h', ha.coefficients']);
legend('Actual','Estimated'); 
xlabel('Coefficient number'); ylabel('Coefficient Value');

[Jan]

I've formatted your code using the "{} code" button. Please care about readable code in the future - thanks!

Whenever you mention an error in the forum, post the complete error message.

Answer 1

[Jan]

The error message is clear:

a = rand([-1 1],a,1);

 Error using rand
 Size inputs must be scalar.

Perhaps you meant randi.