diff --git a/source/source_base/module_external/lapack_connector.h b/source/source_base/module_external/lapack_connector.h
index da90261dd0..ebc558e409 100644
--- a/source/source_base/module_external/lapack_connector.h
+++ b/source/source_base/module_external/lapack_connector.h
@@ -241,9 +241,8 @@ void zhegvx_i(const int* itype,
 // Class LapackConnector provide the connector to fortran lapack routine.
 // The entire function in this class are static and inline function.
 // Usage example:	LapackConnector::functionname(parameter list).
-class LapackConnector
+namespace LapackConnector
 {
-private:
     // Transpose the std::complex matrix to the fortran-form real-std::complex array.
     static inline
     std::complex<double>* transpose(const ModuleBase::ComplexMatrix& a, const int n, const int lda)
@@ -350,7 +349,6 @@ class LapackConnector
 		}
 	}
 
-public:
     // wrap function of fortran lapack routine zheev.
     static inline
     void zheev( const char jobz,
@@ -490,5 +488,5 @@ class LapackConnector
         const char trans_changed = change_trans_NC(trans);
         cherk_(&uplo_changed, &trans_changed, &n, &k, &alpha, A, &lda, &beta, C, &ldc);
     }
-};
+} // namespace LapackConnector
 #endif  // LAPACK_CONNECTOR_HPP
diff --git a/source/source_base/module_external/lapack_wrapper.h b/source/source_base/module_external/lapack_wrapper.h
deleted file mode 100644
index a797c31f6d..0000000000
--- a/source/source_base/module_external/lapack_wrapper.h
+++ /dev/null
@@ -1,494 +0,0 @@
-#ifndef LAPACK_HPP
-#define LAPACK_HPP
-
-/// This is a wrapper of some LAPACK routines.
-/// Direct wrapping of standard LAPACK routines. (column major, fortran style)
-/// including:
-/// 1. hegvd: compute all the eigenvalues and eigenvectors of a generalized Hermitian-definite eigenproblem
-/// 2. heevx: compute the first m eigenvalues and their corresponding eigenvectors of a generalized Hermitian-definite eigenproblem
-/// 3. hegvx: compute the first m eigenvalues and their corresponding eigenvectors of a generalized Hermitian-definite eigenproblem
-/// 4. hegv: compute all the eigenvalues and eigenvectors of a generalized Hermitian-definite eigenproblem
-
-
-#include <iostream>
-extern "C"
-{
-    // =================================================================================
-    // gvd:
-    void dsygvd_(const int* itype, const char* jobz, const char* uplo, const int* n,
-        double* a, const int* lda,
-        const double* b, const int* ldb, double* w,
-        double* work, int* lwork,
-        int* iwork, int* liwork, int* info);
-
-    void chegvd_(const int* itype, const char* jobz, const char* uplo, const int* n,
-             std::complex<float>* a, const int* lda,
-             const std::complex<float>* b, const int* ldb, float* w,
-             std::complex<float>* work, int* lwork, float* rwork, int* lrwork,
-             int* iwork, int* liwork, int* info);
-
-    void zhegvd_(const int* itype, const char* jobz, const char* uplo, const int* n,
-                 std::complex<double>* a, const int* lda, 
-                 const std::complex<double>* b, const int* ldb, double* w,
-                 std::complex<double>* work, int* lwork, double* rwork, int* lrwork,
-                 int* iwork, int* liwork, int* info);
-    // =================================================================================
-
-    // =================================================================================
-    // evx
-    void dsyevx_(const char* jobz, const char* range, const char* uplo, const int* n,
-        double* a, const int* lda,
-        const double* vl, const double* vu, const int* il, const int* iu, const double* abstol,
-        const int* m, double* w, double* z, const int* ldz,
-        double* work, const int* lwork, double* rwork, int* iwork, int* ifail, int* info);
-
-    void cheevx_(const char* jobz, const char* range, const char* uplo, const int* n,
-             std::complex<float> *a, const int* lda,
-             const float* vl, const float* vu, const int* il, const int* iu, const float* abstol,
-             const int* m, float* w, std::complex<float> *z, const int *ldz,
-             std::complex<float> *work, const int* lwork, float* rwork, int* iwork, int* ifail, int* info);
-
-    void zheevx_(const char* jobz, const char* range, const char* uplo, const int* n, 
-                 std::complex<double> *a, const int* lda,
-                 const double* vl, const double* vu, const int* il, const int* iu, const double* abstol, 
-                 const int* m, double* w, std::complex<double> *z, const int *ldz, 
-                 std::complex<double> *work, const int* lwork, double* rwork, int* iwork, int* ifail, int* info);
-    // =================================================================================
-
-
-    // =================================================================================
-    // gvx
-    void dsygvx_(const int* itype, const char* jobz, const char* range, const char* uplo,
-        const int* n, double* A, const int* lda, double* B, const int* ldb,
-        const double* vl, const double* vu, const int* il, const int* iu,
-        const double* abstol, const int* m, double* w, double* Z, const int* ldz,
-        double* work, const int* lwork, int* iwork, int* ifail, int* info);
-
-    void chegvx_(const int* itype,const char* jobz,const char* range,const char* uplo,
-             const int* n,std::complex<float> *a,const int* lda,std::complex<float> *b,
-             const int* ldb,const float* vl,const float* vu,const int* il,
-             const int* iu,const float* abstol,const int* m,float* w,
-             std::complex<float> *z,const int *ldz,std::complex<float> *work,const int* lwork,
-             float* rwork,int* iwork,int* ifail,int* info);
-
-    void zhegvx_(const int* itype,const char* jobz,const char* range,const char* uplo,
-                 const int* n,std::complex<double> *a,const int* lda,std::complex<double> *b,
-                 const int* ldb,const double* vl,const double* vu,const int* il,
-                 const int* iu,const double* abstol,const int* m,double* w,
-                 std::complex<double> *z,const int *ldz,std::complex<double> *work,const int* lwork,
-                 double* rwork,int* iwork,int* ifail,int* info);
-    // =================================================================================
-
-    // =================================================================================
-    // gv
-    void zhegv_(const int* itype,const char* jobz,const char* uplo,const int* n,
-                std::complex<double>* a,const int* lda,std::complex<double>* b,const int* ldb,
-                double* w,std::complex<double>* work,int* lwork,double* rwork,int* info);
-    void chegv_(const int* itype,const char* jobz,const char* uplo,const int* n,
-                std::complex<float>* a,const int* lda,std::complex<float>* b,const int* ldb,
-                float* w,std::complex<float>* work,int* lwork,float* rwork,int* info);
-	void dsygv_(const int* itype, const char* jobz,const char* uplo, const int* n,
-				double* a,const int* lda,double* b,const int* ldb,
-	 			double* w,double* work,int* lwork,int* info);
-    // =================================================================================
-
-}
-
-class LapackWrapper
-{
-  private:
-  public:
-    // wrap function of fortran lapack routine zhegvd. (pointer version)
-    static inline void xhegvd(const int itype,
-                              const char jobz,
-                              const char uplo,
-                              const int n,
-                              double* a,
-                              const int lda,
-                              const double* b,
-                              const int ldb,
-                              double* w,
-                              double* work,
-                              int lwork,
-                              double* rwork,
-                              int lrwork,
-                              int* iwork,
-                              int liwork,
-                              int& info)
-    {
-        // call the fortran routine
-        dsygvd_(&itype, &jobz, &uplo, &n, a, &lda, b, &ldb, w, work, &lwork, iwork, &liwork, &info);
-    }
-
-    // wrap function of fortran lapack routine zhegvd. (pointer version)
-    static inline void xhegvd(const int itype,
-                              const char jobz,
-                              const char uplo,
-                              const int n,
-                              std::complex<float>* a,
-                              const int lda,
-                              const std::complex<float>* b,
-                              const int ldb,
-                              float* w,
-                              std::complex<float>* work,
-                              int lwork,
-                              float* rwork,
-                              int lrwork,
-                              int* iwork,
-                              int liwork,
-                              int& info)
-    {
-        // call the fortran routine
-        chegvd_(&itype, &jobz, &uplo, &n, a, &lda, b, &ldb, w, work, &lwork, rwork, &lrwork, iwork, &liwork, &info);
-    }
-
-    // wrap function of fortran lapack routine zhegvd.
-    static inline void xhegvd(const int itype,
-                              const char jobz,
-                              const char uplo,
-                              const int n,
-                              std::complex<double>* a,
-                              const int lda,
-                              const std::complex<double>* b,
-                              const int ldb,
-                              double* w,
-                              std::complex<double>* work,
-                              int lwork,
-                              double* rwork,
-                              int lrwork,
-                              int* iwork,
-                              int liwork,
-                              int& info)
-    {
-        // call the fortran routine
-        zhegvd_(&itype, &jobz, &uplo, &n, a, &lda, b, &ldb, w, work, &lwork, rwork, &lrwork, iwork, &liwork, &info);
-    }
-
-    // wrap function of fortran lapack routine dsyevx.
-    static inline void xheevx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              double* a,
-                              const int lda,
-                              const double vl,
-                              const double vu,
-                              const int il,
-                              const int iu,
-                              const double abstol,
-                              const int m,
-                              double* w,
-                              double* z,
-                              const int ldz,
-                              double* work,
-                              const int lwork,
-                              double* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        dsyevx_(&jobz,
-                &range,
-                &uplo,
-                &n,
-                a,
-                &lda,
-                &vl,
-                &vu,
-                &il,
-                &iu,
-                &abstol,
-                &m,
-                w,
-                z,
-                &ldz,
-                work,
-                &lwork,
-                rwork,
-                iwork,
-                ifail,
-                &info);
-    }
-
-    // wrap function of fortran lapack routine cheevx.
-    static inline void xheevx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              std::complex<float>* a,
-                              const int lda,
-                              const float vl,
-                              const float vu,
-                              const int il,
-                              const int iu,
-                              const float abstol,
-                              const int m,
-                              float* w,
-                              std::complex<float>* z,
-                              const int ldz,
-                              std::complex<float>* work,
-                              const int lwork,
-                              float* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        cheevx_(&jobz,
-                &range,
-                &uplo,
-                &n,
-                a,
-                &lda,
-                &vl,
-                &vu,
-                &il,
-                &iu,
-                &abstol,
-                &m,
-                w,
-                z,
-                &ldz,
-                work,
-                &lwork,
-                rwork,
-                iwork,
-                ifail,
-                &info);
-    }
-
-    // wrap function of fortran lapack routine zheevx.
-    static inline void xheevx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              std::complex<double>* a,
-                              const int lda,
-                              const double vl,
-                              const double vu,
-                              const int il,
-                              const int iu,
-                              const double abstol,
-                              const int m,
-                              double* w,
-                              std::complex<double>* z,
-                              const int ldz,
-                              std::complex<double>* work,
-                              const int lwork,
-                              double* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        zheevx_(&jobz,
-                &range,
-                &uplo,
-                &n,
-                a,
-                &lda,
-                &vl,
-                &vu,
-                &il,
-                &iu,
-                &abstol,
-                &m,
-                w,
-                z,
-                &ldz,
-                work,
-                &lwork,
-                rwork,
-                iwork,
-                ifail,
-                &info);
-    }
-
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegvx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              std::complex<float>* a,
-                              const int lda,
-                              std::complex<float>* b,
-                              const int ldb,
-                              const float vl,
-                              const float vu,
-                              const int il,
-                              const int iu,
-                              const float abstol,
-                              const int m,
-                              float* w,
-                              std::complex<float>* z,
-                              const int ldz,
-                              std::complex<float>* work,
-                              const int lwork,
-                              float* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        chegvx_(&itype,
-                &jobz,
-                &range,
-                &uplo,
-                &n,
-                a,
-                &lda,
-                b,
-                &ldb,
-                &vl,
-                &vu,
-                &il,
-                &iu,
-                &abstol,
-                &m,
-                w,
-                z,
-                &ldz,
-                work,
-                &lwork,
-                rwork,
-                iwork,
-                ifail,
-                &info);
-    }
-
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegvx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              std::complex<double>* a,
-                              const int lda,
-                              std::complex<double>* b,
-                              const int ldb,
-                              const double vl,
-                              const double vu,
-                              const int il,
-                              const int iu,
-                              const double abstol,
-                              const int m,
-                              double* w,
-                              std::complex<double>* z,
-                              const int ldz,
-                              std::complex<double>* work,
-                              const int lwork,
-                              double* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        zhegvx_(&itype,
-                &jobz,
-                &range,
-                &uplo,
-                &n,
-                a,
-                &lda,
-                b,
-                &ldb,
-                &vl,
-                &vu,
-                &il,
-                &iu,
-                &abstol,
-                &m,
-                w,
-                z,
-                &ldz,
-                work,
-                &lwork,
-                rwork,
-                iwork,
-                ifail,
-                &info);
-    }
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegvx(const int itype,
-                              const char jobz,
-                              const char range,
-                              const char uplo,
-                              const int n,
-                              double* a,
-                              const int lda,
-                              double* b,
-                              const int ldb,
-                              const double vl,
-                              const double vu,
-                              const int il,
-                              const int iu,
-                              const double abstol,
-                              const int m,
-                              double* w,
-                              double* z,
-                              const int ldz,
-                              double* work,
-                              const int lwork,
-                              double* rwork,
-                              int* iwork,
-                              int* ifail,
-                              int& info)
-    {
-        dsygvx_(&itype, &jobz, &range, &uplo, &n, a, &lda, b, &ldb, &vl,
-            &vu, &il, &iu, &abstol, &m, w, z, &ldz, work, &lwork, iwork, ifail, &info);
-    }
-
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegv(const int itype,
-                             const char jobz,
-                             const char uplo,
-                             const int n,
-                             double* a,
-                             const int lda,
-                             double* b,
-                             const int ldb,
-                             double* w,
-                             double* work,
-                             int lwork,
-                             double* rwork,
-                             int& info)
-    {
-        // TODO
-    }
-
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegv(const int itype,
-                             const char jobz,
-                             const char uplo,
-                             const int n,
-                             std::complex<float>* a,
-                             const int lda,
-                             std::complex<float>* b,
-                             const int ldb,
-                             float* w,
-                             std::complex<float>* work,
-                             int lwork,
-                             float* rwork,
-                             int& info)
-    {
-        // TODO
-    }
-    // wrap function of fortran lapack routine xhegvx ( pointer version ).
-    static inline void xhegv(const int itype,
-                             const char jobz,
-                             const char uplo,
-                             const int n,
-                             std::complex<double>* a,
-                             const int lda,
-                             std::complex<double>* b,
-                             const int ldb,
-                             double* w,
-                             std::complex<double>* work,
-                             int lwork,
-                             double* rwork,
-                             int& info)
-    {
-        zhegv_(&itype, &jobz, &uplo, &n, a, &lda, b, &ldb, w, work, &lwork, rwork, &info);
-    }
-};
-#endif // LAPACK_HPP
\ No newline at end of file