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Stephen Wolfram
SEARCH MATHEMATICA 8 DOCUMENTATION
THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
SEE THE
DOCUMENTATION CENTER
FOR THE LATEST INFORMATION.
Mathematica
>
Precision & Accuracy Control
>
Built-in
Mathematica
Symbol
Numerical Precision
Tutorials »
|
$MachinePrecision
Precision
Accuracy
N
See Also »
|
Precision & Accuracy Control
More About »
MachinePrecision
MachinePrecision
is a symbol used to indicate machine-number precision.
MORE INFORMATION
The numerical value of
MachinePrecision
is
$MachinePrecision
.
Precision
[1.]
gives
MachinePrecision
.
MachinePrecision
is the default specification for precision in
N
and other numerical functions.
Approximate real numbers are assumed to have precision specified by
MachinePrecision
if fewer than
$MachinePrecision
explicit digits are entered.
The option setting
WorkingPrecision
->MachinePrecision
specifies that internal computations in numerical functions should be done with machine numbers.
MachinePrecision
is treated as a numeric constant, with attribute
Constant
.
EXAMPLES
CLOSE ALL
Basic Examples
(2)
In[1]:=
Out[1]=
In[2]:=
Out[2]=
MachinePrecision
is treated as an exact numeric quantity:
In[1]:=
Out[1]=
Use like any number:
In[2]:=
Out[2]=
In[3]:=
Out[3]=
The number of bits represented:
In[4]:=
Out[4]=
Scope
(2)
Applications
(3)
Properties & Relations
(4)
SEE ALSO
$MachinePrecision
Precision
Accuracy
N
TUTORIALS
Numerical Precision
MORE ABOUT
Precision & Accuracy Control
New in 5
© 2013 Wolfram Research, Inc.
EXAMPLES
Basic Examples 
Scope 