Add GraphViewModel functions realization

StructureHelperCommon/Models/Functions/GraphPoint.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Functions
+{
+    public class GraphPoint
+    {
+        public double X { get; set; }
+        public double Y { get; set; }
+    }
+}