Added TDist function (#1509)

* Added TDist function

* Fixed misstake

* Fixed failing check

* Small fix

Author: karlkallman

src/EPPlus/FormulaParsing/Excel/Functions/BuiltInFunctions.cs

@@ -262,6 +262,7 @@ public BuiltInFunctions()
             Functions["expon.dist"] = new ExponDotDist();
             Functions["steyx"] = new Steyx();
             Functions["t.dist"] = new TDist();
+            Functions["tdist"] = new TDotDist();
             Functions["t.dist.2t"] = new TDist2t();
             Functions["t.inv"] = new TInv();
             Functions["t.dist.rt"] = new TDistRt();

src/EPPlus/FormulaParsing/Excel/Functions/Statistical/TDotDist.cs

@@ -0,0 +1,33 @@
+/*************************************************************************************************
+  Required Notice: Copyright (C) EPPlus Software AB. 
+  This software is licensed under PolyForm Noncommercial License 1.0.0 
+  and may only be used for noncommercial purposes 
+  https://polyformproject.org/licenses/noncommercial/1.0.0/
+
+  A commercial license to use this software can be purchased at https://epplussoftware.com
+ *************************************************************************************************
+  Date               Author                       Change
+ *************************************************************************************************
+  01/07/2024         EPPlus Software AB           EPPlus v7
+ *************************************************************************************************/
+
+using OfficeOpenXml.FormulaParsing.Excel.Functions.Helpers;
+using OfficeOpenXml.FormulaParsing.Excel.Functions.Metadata;
+using OfficeOpenXml.FormulaParsing.FormulaExpressions;
+using OfficeOpenXml.FormulaParsing.Utilities;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace OfficeOpenXml.FormulaParsing.Excel.Functions.Statistical
+{
+    [FunctionMetadata(
+    Category = ExcelFunctionCategory.Statistical,
+    EPPlusVersion = "7.2.1",
+    Description = "Returns the left-tailed Students t-distribution. The Students t-distribution is used for hypothesis testing with small samples.")]
+
+    internal class TDotDist:TDist
+    {
+    }
+}