whole number and fraction

[DeaD_EyE]

Using decimal.Decimal(float) or fractions.Fraction(float) is not right.
The float you see is wrong. The representation is binary and can't represent all decimal fractions.
Avoid using float as value for Decimal or Fraction.

Compare the results:

print(fractions.Fraction(3, 10)) #right
print(fractions.Fraction('0.3')) #right
print(fractions.Fraction(0.3)) # wrong

The last result is wrong, because the literal 0.3 is converted to a binary fraction, which is very close to 0.3, but it is not real 0.3.

[Skaperen]

i think people just didn't "get" what i was trying to do. and i figured it out. the answer was pretty obvious. but i didn't think of it at first because of my background with C which has a library function to do it which i have used. i just wanted the non-whole part of a float value (or of a decimal.Decimal one, if that's what i get). i just get the whole value and subtract that from the original.

    whole = type(value)(int(value))
    fract = value-whole

but python actually does have a function that does this and returns a 2-tuple with both answers while C's equivalent (same name) returns the fractional part and stores the whole part via the pointer given argument two.

    fract,whole = math.modf(value)