How can I make low pass filter of this?

How can I make low pass filter of this?

The problem: Generate a time series X of length 128 that is a sequence of 128 random numbers pulled from a uniformdistribution with a mean of zero and a range of 1 (i.e. from -0.5 to 0.5).Assume that the time between samples is 0.001 seconds (sampling rate of 1 kHz). Next, create a time series Y, also of length 128, that when convolved with X will act as a 100 Hz low-pass filter (it will attenuate high frequencies, but leave the low frequencies unchanged).

A = rand(1,128)-0.5; % Generate a time series X of length 128 that is a sequence of 128 random numbers pulled from a uniformdistribution with a mean of zero and a range of 1

And then, I am confusing about next step.

Could you help me??

Answer 1

[Image Analyst]

Here's a start

% Construct time axis (called X instead of t for some reason).
X = -0.5 : 0.001 : 0.5
% Construct Y that is the same length as X.
Y = rand(size(X))
% Create filter window:
kernel = ......
% Do the convolution
yFiltered = conv(Y, kernel)

If you need more help, read this:

How do I get help on homework questions on MATLAB Answers? - MATLAB Answers - MATLAB Central

Another hint: create a step function with the edge at 100, then inverse fft it to get the spatial domain kernel that you convolve the signal with.