From 8ea4654de40c6d59d42389c37a35b7315e4c8297 Mon Sep 17 00:00:00 2001
From: Hamlet Tanyavong <34531738+HamletTanyavong@users.noreply.github.com>
Date: Mon, 13 Nov 2023 02:15:17 -0600
Subject: [PATCH] Add test for Jacobian calculations

---
 .../AutoDiff/AutoDiffExtensionsTests.cs           | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/Mathematics.NET.Tests/AutoDiff/AutoDiffExtensionsTests.cs b/tests/Mathematics.NET.Tests/AutoDiff/AutoDiffExtensionsTests.cs
index 39d054e0..2735bc3f 100644
--- a/tests/Mathematics.NET.Tests/AutoDiff/AutoDiffExtensionsTests.cs
+++ b/tests/Mathematics.NET.Tests/AutoDiff/AutoDiffExtensionsTests.cs
@@ -92,6 +92,21 @@ public void Gradient_ScalarFunction_ReturnsGradient(double x, double y, double z
         Assert<Real>.AreApproximatelyEqual(expected, actual, 1e-15);
     }
 
+    [TestMethod]
+    [TestCategory("Vector Calculus")]
+    public void Jacobian_R3VectorFunction_ReturnsJacobian()
+    {
+        var u = _tape.CreateVariableVector(1.23, 0.66, 2.34);
+        Matrix3x3<Real> expected = new(
+            0.775330615737715, -0.5778557672605755, 0.3080621020764366,
+            0.2431083191631576, 0.2431083191631576, 0.2431083191631576,
+            1.450186648348945, 2.197252497498402, -0.6197378839098056);
+
+        var actual = _tape.Jacobian(FX, FY, FZ, u);
+
+        Assert<Real>.ElementsAreApproximatelyEqual(expected, actual, 1e-15);
+    }
+
     //
     // Helpers
     //