From c6b3cabbc67835f255ff1d02d62c4f22027673ab Mon Sep 17 00:00:00 2001
From: Susi Lehtola <susi.lehtola@gmail.com>
Date: Sun, 21 Jan 2024 13:02:38 +0200
Subject: [PATCH] Add function to get number of linearly independent auxiliary
 functions

---
 src/density_fitting.cpp | 4 ++++
 src/density_fitting.h   | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/src/density_fitting.cpp b/src/density_fitting.cpp
index 168a0b3b..343ea4ce 100644
--- a/src/density_fitting.cpp
+++ b/src/density_fitting.cpp
@@ -1144,6 +1144,10 @@ size_t DensityFit::get_Naux() const {
   return Naux;
 }
 
+size_t DensityFit::get_Naux_indep() const {
+  return ab_invh.n_cols;
+}
+
 arma::mat DensityFit::get_ab() const {
   return ab;
 }
diff --git a/src/density_fitting.h b/src/density_fitting.h
index 76588487..f2af04df 100644
--- a/src/density_fitting.h
+++ b/src/density_fitting.h
@@ -159,6 +159,8 @@ class DensityFit {
   size_t get_Norb() const;
   /// Get the number of auxiliary functions
   size_t get_Naux() const;
+  /// Get the number of linearly independent auxiliary functions
+  size_t get_Naux_indep() const;
   /// Get ab_inv
   arma::mat get_ab() const;
   /// Get ab_inv