Tallfestet

Tallfestet

Tallfestet is a term found in some Norwegian technical and educational texts to describe numeric values that are stored and processed with fixed precision. The concept is commonly associated with fixed-point arithmetic, where numbers are represented by integers together with a predetermined scaling factor, rather than by floating-point representations.

Etymology and meaning

The word combines tall, meaning number, with festet, meaning fixed or anchored. In this usage, tallfestet emphasizes that the precision and range of the number are determined in advance by the chosen representation, not by a dynamic floating-point format.

Definition and representation

A tallfestet number is stored as an integer N with an implicit scale factor s, such that the real value equals N divided by s. For example, with a fixed scale of 100, the integer 132 represents the value 1.32. Different implementations may use various scaling schemes, such as a fixed number of fractional bits or an explicit scaling factor chosen at design time.

Applications

Tallfestet representations are common in embedded systems, digital signal processing, and financial computing where deterministic behavior, reproducible rounding, and predictable performance are important. They allow arithmetic to be performed with integer operations, which can be faster and more predictable on certain hardware.

Advantages and limitations

Advantages include deterministic overflow behavior and consistent rounding. Limitations include a limited dynamic range, potential overflow, and the need for careful scaling when interfacing with other number formats or external data.

See also

Fixed-point arithmetic, numeric representation, integer arithmetic, floating-point arithmetic.

Notes

The term tallfestet is not universally standardized and may appear primarily in Norwegian-language contexts or informal documentation.