Export Loom Expression Matrix

For export in Loom format a number of parameters can be specified, see figure 3.3.

Image exporter_loom
Figure 3.3: Exposed parameters for export of expression matrix in Loom format

Matrix export parameters include the following options:

In addition, it is optional to export normalized data.

Export normalized If selected and the matrix has been normalized with Normalize Single Cell Data (see Normalize Single Cell Data), the normalized expressions will be exported instead of the raw counts. If the matrix has not been normalized, the export will fail.

Use compression select among gzip, zip or no compression which is default.

Output file name is the name of the file and can be customized by changing the default pattern in Custom file name.

The Loom exporter creates a Loom file in format version 3.0.0, see https://linnarssonlab.org/loompy/format/index.html for details. In particular:

To load a Loom file "myFile.loom" in Seurat, the following code may be useful:

library(Seurat)
library(loomR)
lfile <- connect(filename="myFile.loom", mode="r", skip.validate=TRUE)
mySeurat <- as.Seurat(lfile)
lfile$close()

To load a Loom file "myFile.loom" in Scanpy, the following code may be useful:

import scanpy as sc
adata = sc.read_loom('myFile.loom',validate=False)