This is documentation for Mathematica 7, which was
based on an earlier version of the Wolfram Language.
 Precision & Accuracy Control Mathematica has sophisticated built-in automatic numerical precision and accuracy control. But for special-purpose optimization of numerical computations, or for studying numerical analysis, Mathematica also allows detailed control over precision and accuracy. N — numerical evaluation to specified precision and accuracy      PrecisionGoal, AccuracyGoal — precision and accuracy goals for computations WorkingPrecision — precision to use inside algorithms      Precision — find the precision of a number Accuracy — find the accuracy of a number      Chop — set sufficiently small numbers or imaginary parts to zero SetPrecision, SetAccuracy — reset precision or accuracy of a number \$MinPrecision, \$MaxPrecision — settable global precision bounds \$MaxExtraPrecision — maximum extra precision to use inside exact algorithms      Machine Numbers MachinePrecision — symbol representing machine precision MachineNumberQ — test if a number is a machine number TUTORIALS Exact and Approximate Results Arbitrary-Precision Numbers Arbitrary-Precision Calculations Machine-Precision Numbers Numerical Precision MORE ABOUT Representation of Numbers Time Measurement & Optimization