| covariates | Test data of covariates |
| Gramm | Get the association between metabolites and microbes |
| metabolites | Test data of metabolome |
| microbes | Test data of microbiome |
| naiveGramm | Corrlation methods of Gramm |
| nlfitGramm | Plot the nonlinear fitting of input data |
| preGramm | Preproccess the metabolome data and microbiome data |