Seismic ray path is analytically calculated assuming a model of the square of slowness.For the model composed of a grid withvalues of model assigned at the grid points,a nonnegative matrix is formed.

• 文章采用平方慢度模型解析计算地震射线传播路径，就模型参数值在网格节点上的情形，可形成一个非负矩阵，这类似单元模型的路径长度矩阵。