When you write `var('alpha')`

you define a symbolic variable, whose role is to serve as an indeterminate in symbolic expressions such as `exp(alpha)/log(alpha+pi)`

. When you write `assume(alpha,'real')`

, you add the hint that this symbolic variable serves as a real indeterminate, the system can use this information during its computations (e.g. when simplifying formulas).

Despite its generic name, `RR`

is not an abstraction representing the reals, but one of the available approximations of the real field, namely `RR`

is made of floating-point numbers with 53 bits of precision, so we are quite far from the symbolic ring, in particular, there is no way to transform a symbol into a floating-point number.