Vai su: http://www.WolframAlpha.com e cerca:
rounding
(seleziona "a class of mathematical ...")
ceiling function
floor function
(seleziona "referring to a mathematical...")
fractional part
(seleziona "a math function")
integer part
(seleziona "a math function")
trunc
ceiling
(seleziona "a math function")
round ( (1, 2, 3)/sum(1, 2, 3)*100)
trunc ( (1, 2, 3)/sum(1, 2, 3)*100)
1/10*round ( (1, 2, 3)/sum(1, 2, 3)*100*10)
mathworld subject rounding
mathworld subject error analysis
accuracy
significant digits
relative error
absolute error
relative difference
significance arithmetic
 ALTRO