You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: vecsim.m
    path of file: ./repos/BTCpredictor
    
    the code of the file until where you have to start completion: %find the similarity between two vectors

function s = vecsim(x,y)
    
    assert(length(x)==length(y),'these vectors are different lengths!');
    assert(~isempty(x),'need a larger vector');
    
 
    
function s = vecsim(x,y)
    
    assert(length(x)==length(y),'these vectors are different lengths!');
    assert(~isempty(x),'need a larger vector');
    
    num = sum((x - mean(x)).*(y-mean(y)));
    den = length(x)*std(x)*std(y);
    
    if (den == 0)
       s = num; %to account for if either vector has std=0          
    else
       s = (num/den);
    end