remotes::install_github('chris-mcginnis-ucsf/DoubletFinder')DF共分成四步：
需要输入的参数：
（1）seu ~ fully processed seurat object (i.e., after NormalizeData, FindVariableGenes, ScaleData, RunPCA, and RunTSNE have all been run)
（2）PCs ~ The number of statistically-significant principal components, specified as a range (e.g., PCs = 1:10)
（3）pN ~ This defines the number of generated artificial doublets, expressed as a proportion of the merged real-artificial data. Default is set to 25%
（4）pK ~ This defines the PC neighborhood size used to compute pANN, expressed as a proportion of the merge
