from Bug (kind-of) in randn() by Arvind
The first number generated by randn() after a seed-reset is always positive!

randomBug.m
XX = zeros(1,1000);

for ii = 1:1000
  seed = round(sum(100*clock)); 
  disp(['seed = ', num2str(seed)]); 
  randn('state', seed); 
  pause(0.01); 
  XX(ii)=randn>0; 
end;


sum(XX)
% Should be roughly 500, instead gives exactly 1000

Contact us at files@mathworks.com