The human brain is also very good at assessing approximate values, like the difference between 10 and 20 cookies, Casasanto says.
A computational formula of approximate value of minimum point and minimum value for some particular functions was infered by interpolation method of equidistant points.
But if your fixed width layout is smaller or lager, you would need to use some approximate values which would again result in pure guessing.
A research of the consruction of rotation matrix without approximate values in close-rang photogrammetry
This paper indicated that the sequence of approximate value of eigenvalue is monotone convergent in the iteration process of matrix iteration method. And also gave examples.
With practice example, the influence of various initial approximate values, observed data errors and the group of observed data on procedure and accuracy of calculation was preliminarily discussed.