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MachinePrecision

MachinePrecision
is a symbol used to indicate machine-number precision.
  • MachinePrecision is the default specification for precision in N and other numerical functions.
  • The option setting WorkingPrecision specifies that internal computations in numerical functions should be done with machine numbers.
MachinePrecision is treated as an exact numeric quantity:
Use like any number:
The number of bits represented:
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MachinePrecision is treated as an exact numeric quantity:
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Use like any number:
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The number of bits represented:
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The machine number approximating :
An arbitrary-precision number approximating to the same precision as machine numbers:
Use machine-number arithmetic to solve a differential equation:
Use double machine precision:
Compare the two solutions:
Evaluate to double machine precision:
Use machine precision for the default precision argument in a function definition:
Make sure computations are carried out with the same precision as machine numbers:
Without fixing the precision, the resulting precision may be lower:
Numbers with just a few digits entered are assumed to have machine precision:
Precision is based on the number of digits when more than $MachinePrecision are entered:
MachinePrecision is a numerical constant while $MachinePrecision evaluates to a number:
$MachinePrecision is the machine-precision approximation to MachinePrecision:
MachinePrecision times the number of bits per digit gives the binary machine precision:
Digits beyond the known precision are represented as Indeterminate:
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