m > n, 列满秩，使用 linv
This work was supported by grant CA-16672 from the National Cancer Institute.
m < n, 行满秩，使用 rinv
rkf45 is primarily designed to solve non-stiff and mildly stiff differential equations when derivative evaluations are inexpensive. rkf45 should generally not be used when the user is demanding high accuracy. 在计算量不大的计算中，rkf45主要用于求解非刚性和轻微刚性的常微分方程。