white gaussian noise and bandwidths

I'm supposed to make a white noise with a variance of 1 and a mean of 2 and another with a variance of 4 and a mean of 2. Then, plot the signal in time and frequency domain. Generate a random signal n1(t) from n(t) that has bandwidth 1Hz by passing n(t) through a low pass filter. Plot n1(t) in time and frequency domain. Repeat for a random signal n4(t) that has bandwidth 4Hz.

I have an error in the line where v=...

what is wrong and does anyone have any advice as to completeing this assignment

%signals
fs = 1e2;%sampling frequency
t = -5:1/fs:5;%time vector
n = randn(1,length(t));%random: mean 0, var 1
mu = 2; 
sig = 4; 
v = exp*fn(n,mu,sig);%random: mean 2, var 4
p = [ zeros(1,floor(length(t)/3)) ones(1,ceil(length(t)/3)+1) zeros(1,floor(length(t)/3))  ];
c = cos(1.5*pi.*t);
g = exp((-pi.*t.^2)/2);

Answer 1

[Star Strider]

The problem is simply with your understanding of the randn funciton. It generates normally-distributed random values with a variance of 1 and a mean of 0. If you want to change those, multiiply or add the desired scalar quantities. So for example:

r = a*randn(1,100)+b;

generates uniformly distributed random numbers with a mean of ‘b’ and a standard deviation of ‘a’.

I’m certain you can take it from there!