Re^3: floating point addition

You are right about bignum. Your bigrat example, though, doesn't work. One needs

perl -Mbigrat -le 'print 20/1 + 1/10'
[download]

لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

Comment on Re^3: floating point addition Download Code

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Re^4: floating point addition by morgon (Priest) on Jan 12, 2015 at 20:15 UTC
`perl -Mbigrat -e ' printf "%20.17f\n", 20/1+1/10;' 20.10000000000000142 perl -Mbigrat -e ' printf "%20.17f\n", 201/10;' 20.10000000000000142` [download] Does not seem to work either - I don't know why not...	[reply] [d/l]
Re^5: floating point addition by choroba (Cardinal) on Jan 12, 2015 at 22:49 UTC
Because `%f` converts the Math::BigRat object to "a floating-point number, in fixed decimal notation" (sprintf). لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l]
Re^6: floating point addition by morgon (Priest) on Jan 13, 2015 at 01:34 UTC
But this remains strange to me: `perl -e 'print 201/10 == 20.10000000000000000 ? "eq" : "ne"' eq perl -Mbigrat -e 'print 201/10 == 20.10000000000000000 ? "eq" : "ne"' eq perl -e 'print 201/10 == 20.10000000000000142 ? "eq" : "ne"' eq perl -Mbigrat -e 'print 201/10 == 20.10000000000000142 ? "eq" : "ne" +' ne` [download] The last two cases is where one can see the difference that bigrat makes, but should the comparison in the second case not yield false?	[reply] [d/l]
Re^7: floating point addition by choroba (Cardinal) on Jan 13, 2015 at 08:39 UTC