The matrices in CwMtx include vectors and squarematrices, where vectors include space vectors and quaternions.
CwMtx 中的矩阵包括向量和方阵,其中向量包括空间向量和四元数。
2
A square real matrix a is called an S2NS matrix, if every matrix with the same sign pattern as a is invertible, and the inverses of all such matrices have the same sign pattern.