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FilledSmallSquare Accuracy[x] gives the effective number of digits to the right of the decimal point in the number x.

FilledSmallSquare Accuracy[x] gives a measure of the absolute uncertainty in the value of x.

FilledSmallSquare With uncertainty dx, Accuracy[x] is -Log[10, dx].

FilledSmallSquare For exact numbers such as integers, Accuracy[x] is Infinity.

FilledSmallSquare Accuracy[x] does not normally yield an integer result, and need not be positive.

FilledSmallSquare For machine-precision numbers, Accuracy[x] gives the same as $MachinePrecision - Log[10, Abs[x]].

FilledSmallSquare Accuracy[0.] is Log[10, $MinMachineNumber].

FilledSmallSquare Numbers entered in the form digits``a are taken to have accuracy a.

FilledSmallSquare If x is not a number, Accuracy[x] gives the minimum value of Accuracy for all the numbers that appear in x.

FilledSmallSquare See Section 3.1.4.

FilledSmallSquare See also: Precision, N, Chop, SetAccuracy.

FilledSmallSquare New in Version 1; modified in 5.0.

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