On Sun, Mar 23, 2014 at 5:23 PM, Joachim Durchholz <[email protected]> wrote: > Am 23.03.2014 22:12, schrieb Christophe Bal: > >>>> You can prove that any valid IEEE float is a rational >> >> >> No ! Why ? Because of the arithmetic rules. You can have approximation to >> do. With decimals, you have to do exact calculations. > > > You two are both right; you just mean different things when you say "Float" > and "Rational". > > Richard refers to the domain, i.e. the list of valid values. > You to the abstract data structure, i.e. the domain plus operations.
And when SymPy says "rational" it means the field. The assumptions system wouldn't very useful if rational only meant integer/integer. We want to be able to say things like rational + rational = rational and rational1*rational2 = rational2*rational1 and so on. Aaron Meurer > > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/532F5EF2.2010405%40durchholz.org. > > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAKgW%3D6Kv%2BEUXb0HqAbicBRC5aLvXCoq3r8nYtx6CLfuumNCVrw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
