Function mathRound

The mathRound() function returns the value of a number rounded to the nearest integer.

If the fractional portion of the argument is greater than 0.5, the argument is rounded to the integer with the next higher absolute value. If it is less than 0.5, the argument is rounded to the integer with the lower absolute value. If the fractional portion is exactly 0.5, the argument is rounded to the next integer in the direction of +∞.

Note: This differs from many languages' round() functions, which often round half-increments away from zero, giving a different result in the case of negative numbers with a fractional part of exactly 0.5.

mathRound(x) is not exactly the same as mathFloor(x + 0.5). When x is -0, or -0.5 ≤ x < 0, mathRound(x) returns -0, while mathFloor(x + 0.5) returns 0. However, neglecting that difference and potential precision errors, mathRound(x) and mathFloor(x + 0.5) are generally equivalent.

mathRound(0.9); // 1
mathRound(5.95); // 6
mathRound(5.5); // 6
mathRound(5.05); // 5
mathRound(-5.05); // -5
mathRound(-5.5); // -5
mathRound(-5.95); // -6
mathRound(-0.9); // -1
Copy