Log, Log10, Log2

Expressions can contain a function that calculates the natural logarithm or logarithm base 10 of an expression or term (function.gms).

X=log(tt);

X=log(y+2);

Eq3..   z=e=log(yy);

X=log10(tt);

X=log10(y+2);

Eq4..   z=e=log10(yy);

These functions are continuous and smooth.  They can be used on data during GAMS calculation or in models.  It's use in .. equations in terms that involve variables requires the model type be NLP or one of the other types that handles nonlinear functions.