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$MachinePrecision

$MachinePrecision
gives the number of decimal digits of precision used for machine-precision numbers.
Hardware machine precision used for floating point computation:
Hardware machine precision used for floating point computation:
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Machine number approximating :
Arbitrary precision number approximating with the same precision as machine numbers:
Make sure computations are carried out with the same precision as machine numbers:
Without fixing the precision, the resulting precision may be lower:
$MachinePrecision evaluates to a number while MachinePrecision is a numerical constant:
$MachinePrecision is the machine precision approximation to MachinePrecision:
Numbers with just a few digits entered are assumed to have machine precision:
Precision is based on the number of digits when more than are entered:
$MachinePrecision times the number of bits per digit gives the binary machine precision:
$MachinePrecision uses arbitrary precision computations with machine precision resolution:
MachinePrecision uses machine number computations:
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