几种新型的灰色模型的代码,包括论文:Research on the novel recursive discrete multivariate grey prediction model and its applicationsX Ma, Z LiuApplied Mathematical Modelling 40 (7-8), 4876-4890Predicting the oil field production using the novel discrete GM (1, N) model.X Ma, Z LiuJournal of Grey System 27 (4),