From 4aa79e072685e78a5e246df35db137313f6304c4 Mon Sep 17 00:00:00 2001
From: Klangina <xyzwhatever668@gmail.com>
Date: Thu, 24 Oct 2024 01:35:56 +0530
Subject: [PATCH] Issue 109 a: - Created R/accnum.R - Added up2ncbi -  Added
 documentation in roxygen

---
 R/accnum.R | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 R/accnum.R

diff --git a/R/accnum.R b/R/accnum.R
new file mode 100644
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+++ b/R/accnum.R
@@ -0,0 +1,35 @@
+
+
+
+
+#' Convert a UniProt ID to an NCBI Entrez Gene ID
+#'
+#' This function takes a single UniProt ID and returns the corresponding NCBI Entrez Gene ID.
+#' It uses the `org.Hs.eg.db` package to perform the mapping.
+#' 
+#' @author Klangina
+#' @param uniprot_id A string representing a single UniProt ID.
+#' @return A string representing the corresponding NCBI Entrez Gene ID. Returns `NA` if no mapping is found.
+#' @examples
+#' \dontrun{
+#'   uniprot_id <- "P04217"
+#'   entrez_id <- up2ncbi(uniprot_id)
+#'   print(entrez_id)
+#' }
+#' @importFrom AnnotationDbi select
+#' @import org.Hs.eg.db
+#' @export
+up2ncbi <- function(uniprot_id) {
+  # Use the select function to map the UniProt ID to an Entrez Gene ID
+  result <- AnnotationDbi::select(org.Hs.eg.db,
+                                  keys = uniprot_id,
+                                  columns = "ENTREZID",
+                                  keytype = "UNIPROT")
+  
+  # Check if the result is not empty and return the first Entrez ID
+  if (nrow(result) > 0 && !is.na(result$ENTREZID[1])) {
+    return(as.character(result$ENTREZID[1]))
+  } else {
+    return(NA)  # Return NA if no mapping is found
+  }
+}
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