Diagonal means either a diagonal matrix (usually a square matrix) in which the entries outside the main diagonal are all zero
Minimum refers to the value in a collection of values that is the least or smallest.
"One way would be to fill the diagonal elements with something lesser than global minimum and then use argsort -"
from question "Python, issue with ties using argsort"
"Even with 32 levels of recusions it will never explode in a rectangular draw area whose diagonal is shorter than 2 32 pixels the limit would be reached only if you are splitting a virtual bezier in a virtually infinite space with floating-point coordinates but you don t intend to draw it directly because you won t have the 1 2 pixel limitation in such space and only if you have set an extreme value for the flatness such that your minimum square sine constant parameter is 1 2 32 or lower"
from question "Fastest way to calculate cubic bezier curves?"