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Reference mapping workflow modeled after Seurat's MapQuery pattern. The current implementation computes gene activity for ATAC query cells, finds anchors to an RNA reference, integrates the query into the reference embedding space, transfers labels, and projects query cells to the reference UMAP.

Usage

RunReferenceMapping(
  srt,
  reference,
  assay = NULL,
  prefix = "ATAC",
  reference_assay = NULL,
  reference_reduction = "pca",
  ref_umap = NULL,
  reference_dims = 1:30,
  reference_label = NULL,
  label_method = c("Seurat", "scOMM"),
  add_gene_activity = TRUE,
  gene_activity_assay = "ACTIVITY",
  dims = 2:30,
  features = NULL,
  reduction_project_method = "pcaproject",
  k.anchor = 5,
  k.filter = 200,
  k.score = 30,
  k.weight = 100,
  projection_method = c("model", "knn"),
  nn_method = NULL,
  k = 30,
  distance_metric = "cosine",
  vote_fun = "mean",
  evaluate = FALSE,
  truth_col = NULL,
  tool_name = NULL,
  rare_threshold = 0.05,
  scomm_python = NULL,
  scomm_hidden_nodes = c(128, 64),
  scomm_epochs = 10,
  scomm_batch_size = 32,
  scomm_threshold = 0.5,
  scomm_seed = 11,
  verbose = TRUE
)

Arguments

srt

A Seurat object.

reference

RNA reference Seurat object used for mapping.

assay

Which assay to use. If NULL, the default assay of the Seurat object will be used. When the object also contains ChromatinAssay, the default assay and additional ChromatinAssay will be preprocessed sequentially.

prefix

Prefix used to resolve ATAC reductions. Default is "ATAC".

reference_assay

Assay used in the reference object.

reference_reduction

Reduction used in the reference object.

ref_umap

UMAP reduction in the RNA reference used for query projection.

reference_dims

Dimensions used from the reference reduction.

reference_label

Metadata column in the reference used as transfer labels.

label_method

Label-transfer backend used after anchor mapping. One of "Seurat" or "scOMM".

add_gene_activity

Whether to calculate a gene activity assay for the query.

gene_activity_assay

Name of the gene activity assay used for mapping.

dims

Query reduction dimensions used by TransferData.

features

Features used by FindTransferAnchors. If NULL, reference variable features are used.

reduction_project_method

Anchor projection method. Default is "pcaproject" for RNA reference mapping.

k.anchor, k.filter, k.score, k.weight

Parameters passed to Seurat anchor finding/integration.

projection_method, nn_method, k, distance_metric, vote_fun

Passed to RunKNNMap for UMAP projection and neighbor voting.

evaluate

Whether to compute mapping metrics against a truth label.

truth_col

Metadata column in srt used as the truth label when evaluate = TRUE.

tool_name

Name used to store detailed results in srt@tools.

rare_threshold

Maximum class proportion used to define rare classes when calculating rare_recall.

scomm_python

Optional Python binary used by the scOMM backend. If NULL, SCOP_SCOMM_PYTHON is consulted and reticulate defaults are used otherwise.

scomm_hidden_nodes, scomm_epochs, scomm_batch_size, scomm_threshold, scomm_seed

Parameters passed to the optional scOMM backend.

verbose

Whether to print the message. Default is TRUE.

Value

A query Seurat object mapped into the RNA reference space.