try to find the gene modules, but get error as following
pr_test_res <- graph_test(my.cds.s1, neighbor_graph="principal_graph", cores=4)
pr_deg_ids <- row.names(subset(pr_test_res, q_value < 0.05))
gene_module_df <- find_gene_modules(my.cds.s1[pr_deg_ids,], resolution=0.001)
Error in array(x, c(length(x), 1L), if (!is.null(names(x))) list(names(x), :
'data' must be of a vector type, was 'NULL'