nround

nround is a term used in numerical computation to denote a rounding operation that produces a value with n digits of precision. The exact behavior of nround is not standardized and can vary by language or library. In some contexts, n refers to the number of digits to the right of the decimal point (decimal places); in others, it refers to the number of significant digits.

Typical implementations provide a function that accepts at least two arguments: the numeric value x and an integer n. An optional rounding mode may specify how to handle halfway cases, with common modes including round half up, round half to even, or toward zero.

Because there is no universal standard, real-world behavior depends on the source. Many languages offer a built-in round-like function that can be configured for the number of decimal places; in such cases nround is either an alias for that function or a name used in documentation to emphasize the "n" parameter.

Examples (decimal places): nround(3.14159, 2) yields 3.14; nround(3.5, 0) yields 4 under typical half-up rounding.

Examples (significant digits) vary by implementation; some definitions round to n significant digits rather than decimal places.

Applications include numerical formatting, data presentation, and numerical analysis where controlled precision is required. Potential pitfalls include floating-point errors, inconsistent rounding across platforms, and ambiguity about n's meaning.

See also: round, floor, ceil, bankers rounding, significant figures.