Accuracy[x]Notice that the result could be slightly different from the result obtained in WMA, due to differences in the internal representation of the real numbers.
Accuracy of a real number is estimated from its value and its precision:
Accuracy[3.1416`2]
Notice that the value is not exactly equal to the obtained in WMA: This is due to the different way in which Precision is handled in SymPy.
Accuracy for exact atoms is Infinity:
Accuracy[1]
Accuracy[A]
For Complex numbers, the accuracy is estimated as (minus) the base-10 log
of the square root of the squares of the errors on the real and complex parts:
z=Complex[3.00``2, 4.00``2];
Accuracy[z] == -Log[10, Sqrt[10^(-2 Accuracy[Re[z]]) + 10^(-2 Accuracy[Im[z]])]]
Accuracy of expressions is given by the minimum accuracy of its elements:
Accuracy[F[1, Pi, A]]
Accuracy[F[1.3, Pi, A]]
Accuracy for the value 0 is a fixed-precision Real number:
0``2
Accuracy[0.``2]
For 0.`, the accuracy satisfies:
Accuracy[0.`] == $MachinePrecision - Log[10, $MinMachineNumber]
In compound expressions, the Accuracy is fixed by the number with
the lowest Accuracy:
Accuracy[{{1, 1.`},{1.``5, 1.``10}}]
See also Precision.