Index: tol/stdlib/math/stat/models/bayesian/arima/_arma_process.tol
===================================================================
--- tol/stdlib/math/stat/models/bayesian/arima/_arma_process.tol	(revision 8dcdd01ff0772b3e30ff752eec5b4df8a1497a24)
+++ tol/stdlib/math/stat/models/bayesian/arima/_arma_process.tol	(revision 7483990d2ec001276b3946c752e0031d48b3d143)
@@ -10,4 +10,35 @@
 [[
   Text _.autodoc.description = "Methods related with ARMA process";
+  
+  ////////////////////////////////////////////////////////////////////////////
+  Text _.autodoc.member.ACOV =
+  "Returns theoretical autocovariance function from 0 to given order";
+  Matrix ACOV(Polyn ar, Polyn ma, Real order)
+  ////////////////////////////////////////////////////////////////////////////
+  {
+    Matrix acov = ARMATACov(ar,ma,order+1)
+  };
+
+  ////////////////////////////////////////////////////////////////////////////
+  Text _.autodoc.member.ACF =
+  "Returns theoretical autocorrelation function from 0 to given order";
+  Matrix ACF(Polyn ar, Polyn ma, Real order)
+  ////////////////////////////////////////////////////////////////////////////
+  {
+    Matrix acov = ARMATACov(ar,ma,order+1);
+    Matrix acf = acov * 1/MatDat(acov,1,1)
+  };
+
+  ////////////////////////////////////////////////////////////////////////////
+  Text _.autodoc.member.PACF =
+  "Returns theoretical partial autocorrelation function from 0 to given order";
+  Matrix ACF(Polyn ar, Polyn ma, Real order)
+  ////////////////////////////////////////////////////////////////////////////
+  {
+    Matrix acov = ARMATACov(ar,ma,order+1);
+    Matrix acf = acov * 1/MatDat(acov,1,1);
+    Matrix fi = DurbinAutoReg(Sub(acf,2,1,order,1),order);
+    Matrix pacf = Col(1) << Tra(SubDiag(fi,0))
+  };
 
   ////////////////////////////////////////////////////////////////////////////
@@ -436,5 +467,7 @@
       _0.5_m_log2_PI_s2 - 0.5*_.m*VMatMoment(a,2)/_.s2
     }
-  ]])}
+  ]])};
+
+  
 
 ]];