function pdf=dfnorm(u, sigsq, samples) 
% dfnorm(u, sigsq, samples)  Generates a Gaussian pdf with mean u and  
%    variance sigma squared (sigsq).  samples sets the size of the numerical 
%    representation, and is optional.  The default sample size is 1000. 
if nargin==2 
   samples=1000; 
end 
if sigsq<=0 
   error('invalid value for sigsq') 
end 
sigma=sqrt(sigsq); 
x=[u-5*sigma:10*sigma/samples:u+5*sigma]; 
p=exp(-((x-u).^2)./(2*(sigma^2)))./(sqrt(2*pi)*sigma); 
pdf=[0 1;x' p']; 
if ispf(pdf)==0 
   p=p./ttlprob(pdf); 
   pdf=[0 1; x' p']; 
end