countsSampling          countsSampling: Downsampling the read counts in
                        a cell
estDropoutNum           estDropoutNum: Estimate dropout gene number in
                        a cell
normalization           normalization: Normalization for single-cell
                        RNA-seq data
scRecover               scRecover: Imputation for single-cell RNA-seq
                        data
scRecoverTest           scRecoverTest: A test dataset for scRecover
