Figure 1: “Theorem of Pieter Goras” - an aproximation formula
A transformation of a vector to an absolute value is often demanded in a radar unit and therefore the application of the law of Pythagoras. Unfortunately, the calculation of the square root is in the assembler or in a mathematical hardware wiring electronic very complicatedly. The problem is, that the calculation of a square root needs different steps depending on the values a and b.
Therefore an approximation formula is used
whose precision is sufficient in most cases, and this procedure provides,
that all possible values of a and b
need the same number of program-steps (i.e.: it needs the same time!):
The sum of the length of the longer side and half the length of the
shorter side is approximately the length of the hypotenuse.
c ≈ a + 0,5 • b