mean(v)={
  vecsum(v)/#v
};
stdev(v,mu="")={
  if(mu=="",mu=mean(v));
  sqrt(sum(i=1,#v,(v[i]-mu)^2))/#v
};
histogram(v,bins=16,low=0,high=1)={
  my(u=vector(bins),width=(high-low)/bins);
  for(i=1,#v,u[(v[i]-low)\width+1]++);
  u
};
show(n)={
  my(v=vector(n,i,random(1.)),mu=mean(v),s=stdev(v,mu),h=histogram(v),sz=ceil(n/50/16));
  for(i=1,16,for(j=1,h[i]\sz,print1("#"));print());
  print("Mean: "mu);
  print("Stdev: "s);
};
show(100);
show(1000);
show(10000);