1 files changed, 15 insertions, 0 deletions
diff --git a/searchlib/src/vespa/searchlib/expression/simple_interpolate.h b/searchlib/src/vespa/searchlib/expression/simple_interpolate.h
new file mode 100644
index 00000000000..92cc29904eb
--- /dev/null
+++ b/searchlib/src/vespa/searchlib/expression/simple_interpolate.h
@@ -0,0 +1,15 @@
+// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <vector>
+
+namespace search::expression {
+
+/*
+ * Perform simple interpolation for interpolatedlookup function
+ * in grouping expression.
+ */
+double simple_interpolate(const std::vector<double>& v, double lookup) noexcept;
+
+}