diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt
index 7f3d7b2..3db6544 100644
--- a/example/CMakeLists.txt
+++ b/example/CMakeLists.txt
@@ -33,4 +33,4 @@ add_example(array_ex OFF)
 add_example(gmt_ex OFF)
 add_example(gnuplot_ex OFF)
 add_example(stl_io_ex OFF)
-add_example(ply_io_ex ON)
\ No newline at end of file
+add_example(ply_io_ex OFF)
\ No newline at end of file
diff --git a/lib/core/matrix.h b/lib/core/matrix.h
index 318ea17..8a11226 100644
--- a/lib/core/matrix.h
+++ b/lib/core/matrix.h
@@ -36,14 +36,14 @@ namespace gctl
 	template <typename MatValType> class matrix;
 
 	/*
-	 * Here we define some commonly used array types.
+	 * Here we define some commonly used matrix types.
 	 */
-	typedef matrix<int> _2i_matrix; ///< 2-D integer array
-	typedef matrix<float> _2f_matrix; ///< 2-D single-precision floating-point array
-	typedef matrix<double> _2d_matrix; ///< 2-D double-precision floating-point array
-	typedef matrix<std::string> _2s_matrix; ///< 2-D string array
-	typedef matrix<std::complex<float> > _2cf_matrix; ///< 1-D complex float array
-	typedef matrix<std::complex<double> > _2cd_matrix; ///< 1-D complex double array
+	typedef matrix<int> _2i_matrix; ///< 2-D integer matrix
+	typedef matrix<float> _2f_matrix; ///< 2-D single-precision floating-point matrix
+	typedef matrix<double> _2d_matrix; ///< 2-D double-precision floating-point matrix
+	typedef matrix<std::string> _2s_matrix; ///< 2-D string matrix
+	typedef matrix<std::complex<float> > _2cf_matrix; ///< 1-D complex float matrix
+	typedef matrix<std::complex<double> > _2cd_matrix; ///< 1-D complex double matrix
 
 	/**
 	 * @brief      二维数组模版
@@ -259,13 +259,20 @@ namespace gctl
 		 * @param odr  计算行或列的平均值
 		 */
 		void mean(array<MatValType> &m, matrix_order_e odr = RowMajor);
+
+		/**
+		 * @brief      按行或列归一化矩阵元素
+		 *
+		 * @param odr  计算行或列的平均值
+		 */
+		void normalize(matrix_order_e odr = RowMajor);
 		
 		/**
 		 * @brief      计算矩阵的模长
 		 * 
 		 * @param n_type 模的类型
 		 */
-		double norm(norm_type_e n_type = L2) const;
+		double module(norm_type_e n_type = L2) const;
 
 		/**
 		 * @brief Set elements' value as a sequent.
@@ -829,7 +836,47 @@ namespace gctl
 	}
 
 	template <typename MatValType>
-	double matrix<MatValType>::norm(norm_type_e n_type) const
+	void matrix<MatValType>::normalize(matrix_order_e odr)
+	{
+		if (odr == RowMajor)
+		{
+			for (size_t i = 0; i < row_length; i++)
+			{
+				MatValType sum = 0.0;
+				for (size_t j = 0; j < col_length; j++)
+				{
+					sum += val[i][j]*val[i][j];
+				}
+				sum = sqrt(sum);
+
+				for (size_t j = 0; j < col_length; j++)
+				{
+					val[i][j] /= sum;
+				}
+			}
+		}
+		else // ColMajor
+		{
+			for (size_t j = 0; j < col_length; j++)
+			{
+				MatValType sum = 0.0;
+				for (size_t i = 0; i < row_length; i++)
+				{
+					sum += val[i][j]*val[i][j];
+				}
+				sum = sqrt(sum);
+
+				for (size_t i = 0; i < row_length; i++)
+				{
+					val[i][j] /= sum;
+				}
+			}
+		}
+		return;
+	}
+
+	template <typename MatValType>
+	double matrix<MatValType>::module(norm_type_e n_type) const
 	{
 		MatValType nval = (MatValType) 0;
 		if (n_type == L0)