[lambdatronics]

It's a real mess. I ran into an issue recently because I'm dealing with probability distributions in terms of several sets of general curvilinear coordinate systems. In a context like this, the usual abuse of notation in which the function is identified by which arguments go into it just doesn't work. I have a probability density in Cartesian coordinates expressed as a function of (say) elliptical coordinates -- which differs by the Jacobian from the probability density in elliptical coordinates.