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Mathematica
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Precision & Accuracy Control
>
Built-in
Mathematica
Symbol
Numerical Precision
The Uncertainties of Numerical Mathematics
Tutorials »
|
Precision
RealExponent
N
Chop
SetAccuracy
AccuracyGoal
WorkingPrecision
NumberMarks
See Also »
|
Numerical Evaluation & Precision
Precision & Accuracy Control
Representation of Numbers
More About »
Accuracy
Accuracy
[
x
]
gives the effective number of digits to the right of the decimal point in the number
x
.
MORE INFORMATION
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
]
is
Infinity
.
Accuracy
[
x
]
does not normally yield an integer result, and need not be positive.
For any approximate number
x
,
Accuracy
[
x
]
is equal to
Precision
[
x
]-
RealExponent
[
x
]
.
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
.
»
EXAMPLES
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Basic Examples
(3)
Machine-precision number:
In[1]:=
Out[1]=
Arbitrary-precision number:
In[1]:=
Out[1]=
Exact number:
In[1]:=
Out[1]=
Scope
(4)
Generalizations & Extensions
(1)
Applications
(2)
Properties & Relations
(2)
Neat Examples
(1)
SEE ALSO
Precision
RealExponent
N
Chop
SetAccuracy
AccuracyGoal
WorkingPrecision
NumberMarks
TUTORIALS
Numerical Precision
The Uncertainties of Numerical Mathematics
MORE ABOUT
Numerical Evaluation & Precision
Precision & Accuracy Control
Representation of Numbers
New in 1 | Last modified in 5
© 2008 Wolfram Research, Inc.
EXAMPLES
Basic Examples 
Scope 