I have a function that gives me log(y) and derivative of log(y) call it dlog(y) . However I am interested in knowing y and derivative of y call it dy. Now I get dy as follows

I get under/overflow problems when y is close to zero. Any suggestions?Code:dy = exp( log (y)) * dlog ( y) which is equaivalent to dy = exp( log (y)) * (1/ y * dy) which simplifies to dy = dy