Revision 9 as of 2005-01-09 16:52:43

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I discovered this when my students were creating a fraction class. 7/4 = 1 however -7/4 = -2 It seems to me the second result should be -1 It appears it is using the floor function but it isn't what my students wanted nor can I think of when anyone would want this result. Anyone know why? Thanks for any help Terry S - tscott@fisher.unco.edu


That is what floor division does, it reduces the value to the next lowest whole number. If you want to separate the whole number and fractional part, use math.modf:

from __future__ import division
import math
print math.modf(25/12)
--> (0.08333, 2.0)
print math.modf(-25/12)
--> (-0.08333, -2.0)

#to just print the whole number as an int:
print int(math.modf(25/12)[1])


Please see the Python Programming FAQ, [http://www.python.org/doc/faq/programming.html#why-does-22-10-return-3 question 1.3.2], for an explanation.

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