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data-raw/README.md

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+This directory contains scripts to download and preprocess data used within the rOpenScPCA package.
+There are also notebooks that explore some of the prepared datasets for exploration.
+
+## Building Gene References
+
+- The `build_gene_references.R` script creates a table of Ensembl id to gene symbol references.
+It starts with the example ScPCA-formatted SCE object stored in test data, extracting the table of gene ids and gene symbols.
+This is combined with the reference information extracted from example 10x Genomics datasets.
+The full table is saved in `data/scpca_gene_reference.rda`.
+
+- The `explore_gene_references.Rmd` notebook explores the resulting gene references table a bit to see where some of the conversions differ among different references.