Basic Examples (2) 

All rational numbers result in recurring decimal digits:

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RecurringDecimalForm displays this in a more compact notation:

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Scope (5) 

RecurringDecimalForm accepts any input that is numeric:

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RecurringDecimalForm ignores repeating zeros:

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For numeric quantities, a repeating sequence in the final digits (excluding the last digit, which is subject to rounding) is assumed to be recurring:

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For exact numeric quantities that are not explicitly Rational, RecurringDecimalForm searches the first $MaxExtraPrecision digits:

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Recurring digits can be found in other number bases:

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Options (3) 

There are several notations for the display of recurring digits used in different parts of the world:

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Digit sequences that repeat at least three times are assumed to be recurring:

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The option "MinRepeats" controls this sensitivity:

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By default, the final digit is assumed to be subject to rounding and is ignored:

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In some circumstances, more digits are affected by rounding:

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You can ignore more digits with "RoundingDigits":

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Possible Issues (4) 

By default, the final digit is assumed to be subject to rounding and is ignored:

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In some circumstances, more digits are affected by rounding:

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In these circumstances, RecurringDecimalForm will not recognize the repeat:

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You can ignore more digits with "RoundingDigits":

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