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Documentation / Mathematica / Built-in Functions / Numerical Computation / Numerical Precision /

Precision

FilledSmallSquare Precision[x] gives the effective number of digits of precision in the number x.

FilledSmallSquare Precision[x] gives a measure of the relative uncertainty in the value of x.

FilledSmallSquare With absolute uncertainty dx, Precision[x] is -Log[10, dx/x].

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

FilledSmallSquare Precision[x] does not normally yield an integer result.

FilledSmallSquare For machine-precision numbers Precision[x] yields MachinePrecision.

FilledSmallSquare Numbers entered in the form digits`p are taken to have precision p.

FilledSmallSquare Numbers such as 0``a whose overall scale cannot be determined are treated as having zero precision.

FilledSmallSquare Numbers with zero precision are output in StandardForm as , where is their accuracy.

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

FilledSmallSquare See Section 3.1.4.

FilledSmallSquare See also: Accuracy, N, Chop, SetPrecision, MachineNumberQ.

FilledSmallSquare New in Version 1; modified in 5.0.

Further Examples