• Accuracy[x] gives the effective number of digits to the right of the decimal point in the number x.
• Accuracy[x] gives a measure of the absolute uncertainty in the value of x.
• With uncertainty dx, Accuracy[x] is -Log[10, dx].
• For exact numbers such as integers, Accuracy[x]
• Accuracy[x] does not normally yield an integer result, and need not be positive.
• For machine-precision numbers, Accuracy[x] gives the same as $MachinePrecision - Log[10, Abs[x]].
• Accuracy[0.] is Log[10, $MinMachineNumber].
• Numbers entered in the form digits``a are taken to have accuracy a.
• If x is not a number, Accuracy[x] gives the minimum value of Accuracy for all the numbers that appear in x.
• New in Version 1; modified in 5.