1 files changed, 13 insertions, 0 deletions
diff --git a/gn2/wqflask/marker_regression/exceptions.py b/gn2/wqflask/marker_regression/exceptions.py
new file mode 100644
index 00000000..8c7e822b
--- /dev/null
+++ b/gn2/wqflask/marker_regression/exceptions.py
@@ -0,0 +1,13 @@
+"""Mapping Exception classes."""
+
+class NoMappingResultsError(Exception):
+    "Exception to raise if no results are computed."
+
+    def __init__(self, trait, dataset, mapping_method):
+        self.trait = trait
+        self.dataset = dataset
+        self.mapping_method = mapping_method
+        self.message = (
+            f"The mapping of trait '{trait}' from dataset '{dataset}' using "
+            f"the '{mapping_method}' mapping method returned no results.")
+        super().__init__(self.message, trait, mapping_method)