weighted correlation in Q?

I know there is a correlation function in Q.  https://code.kx.com/q/ref/cor/

Is there a “weighted correlation”? 

There is no inbuilt weighted correlation, but you can easily implement Pearson Weighted Correlation as follows

wcov: {[x;y;w] w wavg (x-w wavg x)*y-w wavg y}    // weighted covariance

wcor: {[x;y;w] wcov[x;y;w]%sqrt wcov[x;x;w]*wcov[y;y;w]}   // weighted correlation

-Ajay