Added jacobian mode

docs/userDocs/source/user/tutorials.rst

@@ -89,6 +89,36 @@ if we want to differentiate w.r.t to the first two elements of the array along w
 write `clad::hessian(f_arr, z[0:1])`.
 
 
+The Jacobian Mode 
+
+Clad can produce Jacobian of a function using its reverse mode. It returns the jacobian matrix as a flaattened vector with
+elements arranged in row-major format.
+
+.. code-block:: cpp
+   #include "clad/Differentiator/Differentiator.h"
+   #include<iostream>
+
+   void f(doubl x, double y, double z, double *output) {
+   output[0] = x*y;
+   output[1] = y * y * x;
+   output[2] = 6 * x * y * z;
+   }
+
+   int main() {
+   auto f_jac = clad::jacobian(f);
+
+   double jac[9] = {0};
+   double output[3] = {0};
+   f_jac.execute(3, 4, 5, output, jac);
+    std::cout << jac[0] << " " << jac[1] << std::endl
+              << jac[2] << " " << jac[3] << std::endl
+              << jac[4] << " " << jac[5] << std::endl
+              << jac[6] << " " << jac[7] << std::endl
+              << jac[8]<<std::endl;
+   }
+
+   
+