define double theta[2] k lambda nu jyperk 
let nu 
let theta 
let theta theta*pi|180|3600|2.|sqrt(log(2.0)) 
let lambda 2.99792458e8|nu*1e-9 
say 'lambda' 'theta[1]' 'theta[2]' 
let jyperk 2.0*1.38e3*pi*theta[1]*theta[2]|lambda^2 
say "K per Jy" '1|jyperk' 
say "mJy per K" '1e3*jyperk'