fix bug in SetDatExpr function

  # correlate all cells:

  cor_list <- list(); pval_list <- list(); fdr_list <- list()

  # testing other correlation function:

  # correlation:

  temp <- Hmisc::rcorr(as.matrix(trait_df), as.matrix(MEs), type=cor_method)

  # get the coefficient & p-val

  cur_cor <- temp$r[traits,mods]

  cur_p <- temp$P[traits,mods]

  # get parameters from seurat object

  params <- GetWGCNAParams(seurat_obj, wgcna_name)

  genes_use <- GetWGCNAGenes(seurat_obj, wgcna_name)

  modules <- GetModules(seurat_(bj, wgcna_name))

  modules <- GetModules(seurat_obj, wgcna_name))

  assay <- params$metacell_assay

  print('n_genes:')

  selected_modules$framecolor <- ifelse(selected_modules$gene_name %in% label_genes, 'black', selected_modules$color)

  # melt TOM into long format

  edge_df <- subset_TOM %>% melt

  edge_df <- subset_TOM %>% reshape2::melt()

  print(dim(edge_df))

  # set color of each edge based on value:

    gene1 = as.character(edge_df[i,'Var1'])

    gene2 = as.character(edge_df[i,'Var2'])

    col1 <- modules %>% subset(gene_name == gene1) %>% .$color

    col2 <- modules %>% subset(gene_name == gene2) %>% .$color

    col1 <- selected_modules[selected_modules$gene_name == gene1, 'color']

    col2 <- selected_modules[selected_modules$gene_name == gene2, 'color']

    if(col1 == col2){

      col = col1

    subset(edge_df, color == 'grey90'),

    subset(edge_df, color != 'grey90')

  )

  head(edge_df)

  # set alpha of edges based on kME

  edge_df$color_alpha <- ifelse(