mathjs/docs/reference/functions/round.md

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Function round #

Round a value towards the nearest integer. For matrices, the function is evaluated element wise.

Syntax #

math.round(x)
math.round(x, n)

Parameters #

Parameter	Type	Description
x	number | BigNumber | Fraction | Complex | Array | Matrix	Number to be rounded
n	number | BigNumber | Array	Number of decimals Default value: 0.

Returns #

Type	Description
number | BigNumber | Fraction | Complex | Array | Matrix	Rounded value

Examples #

math.round(3.2);              // returns number 3
math.round(3.8);              // returns number 4
math.round(-4.2);             // returns number -4
math.round(-4.7);             // returns number -5
math.round(math.pi, 3);       // returns number 3.142
math.round(123.45678, 2);     // returns number 123.46

var c = math.complex(3.2, -2.7);
math.round(c);                // returns Complex 3 - 3i

math.round([3.2, 3.8, -4.7]); // returns Array [3, 4, -5]

See also #

ceil, fix, floor