signifikanden

Signifikanden is the plural of Signifikand, a mathematical term used in discussions of floating-point numbers and scientific notation. The signifikand refers to the part of a number that contains its significant digits, in contrast to the exponent that encodes its scale.

In decimal scientific notation, a number is written as a significand times a base to an exponent, for example 6.022 × 10^23, where 6.022 is the significand and 23 is the exponent. The significand captures the precise digits that convey the value, while the exponent indicates the scale of the number.

In computing, floating-point representations separate a sign, an exponent, and a significand. The significand (often called the mantissa in some contexts) represents the significant digits of the number. In normalized binary floating point, the significand has an implicit leading 1, so the actual value is 1.fraction, with the stored fraction representing the remaining bits. The precision of a floating-point value is determined by the number of digits in its significand.

The term is primarily used in German-language texts; in English, the corresponding terms are significand or mantissa. The significand is the quantitative core of the value and is subject to rounding and rounding-related errors during arithmetic operations.

See also: Mantissa; Floating-point number; Scientific notation; Precision.