diff --git a/example/text_io_ex.cpp b/example/text_io_ex.cpp
index 6169cf9..d32cbba 100644
--- a/example/text_io_ex.cpp
+++ b/example/text_io_ex.cpp
@@ -32,7 +32,7 @@ using namespace gctl;
 
 int main(int argc, char const *argv[]) try
 {
-
+/*
     dsv_io tc;
     tc.set_delimeter('|');
     tc.load_text("tmp/world_data", ".txt", BothHead);
@@ -49,16 +49,16 @@ int main(int argc, char const *argv[]) try
     //name.show(std::cout, ',');
 
     tc.save_csv("out");
+*/
 
-/*
     geodsv_io tc;
     tc.load_text("tmp/topo", ".txt", ColumnHead);
-    tc.cell(0, 1, std::string("x (m)"));
-    tc.cell(0, 2, std::string("y (m)"));
-    tc.cell(0, 3, std::string("elevation (m)"));
+    tc.cell(std::string("x (m)"), 0, 1);
+    tc.cell(std::string("y (m)"), 0, 2);
+    tc.cell(std::string("elevation (m)"), 0, 3);
 
     array<point3dc> topo;
-    tc.get_column_point3dc(1, 2, 3, topo);
+    tc.get_column_point3dc(topo, 1, 2, 3);
 
     std::clog << std::setprecision(11) << topo.front().z << "\n";
     std::clog << topo.back().x << "," << topo.back().y << "," << topo.back().z << "\n";
@@ -66,7 +66,14 @@ int main(int argc, char const *argv[]) try
     display_vector(tc.get_annotoations(), std::clog, '\n');
     display_vector(tc.get_head_records(), std::clog, '\n');
 
-    tc.column_output("C3", Disable);
+    //tc.column_output("C3", Disable);
+    
+    array<double> elev;
+    tc.get_column(elev, "elevation (m)");
+    elev.for_each([](double &d, size_t i){d += 100.0;});
+
+    tc.add_column(-1, "elev_plus");
+    tc.fill_column(elev, "elev_plus");
 
     _1s_vector s = tc.get_tags();
     s.push_back("Elev = 1000");
@@ -74,11 +81,11 @@ int main(int argc, char const *argv[]) try
     tc.save_csv("out");
 
     double c = 4.25242153654;
-    tc.cell(2, 1, c, 12);
+    tc.cell(c, 2, 1, 12);
     std::clog << std::setprecision(12) << tc.cell<double>(2, 1) << "\n";
 
     tc.info();
-*/
+
     return 0;
 }
 catch(std::exception &e)
diff --git a/lib/core/array.h b/lib/core/array.h
index 5bd23d7..5c0a5ad 100644
--- a/lib/core/array.h
+++ b/lib/core/array.h
@@ -511,27 +511,27 @@ namespace gctl
 		 * @param[in]  np2          Standard deviation (Gauss) or hig bound value (Even).
 		 * @param[in]  mode         Random types. 'RdNormal' for Gaussian distributed numbers and 
 		 * 'RdUniform' for even distributed numbers.
-		 * @param[in] seed          Random seed.
+		 * @param[in] seed          Random seed. Input 0 to select the seed based on the current time.
 		 */
 		void random_float(ArrValType np1, ArrValType np2, random_type_e mode = RdNormal, unsigned int seed = 0);
 
 		/**
 		 * @brief      Initialize the array with selected random types.
 		 *
-		 * @param[in]  np1          Mean (Gauss) or low bound value (Even)
-		 * @param[in]  np2          Standard deviation (Gauss) or hig bound value (Even).
-		 * @param[in] seed          Random seed.
+		 * @param[in]  np1          Low bound value.
+		 * @param[in]  np2          Hig bound value.
+		 * @param[in] seed          Random seed. Input 0 to select the seed based on the current time.
 		 */
 		void random_int(ArrValType np1, ArrValType np2, unsigned int seed = 0);
 
 		/**
 		 * @brief Set elements' value as a sequent.
 		 * 
-		 * @param st_val  Start value.
-		 * @param inc Increasement.
-		 * @param st_id Start index.
-		 * @param size Operating size.
-		 * @param space Indexing spacing.
+		 * @param st_val  Start value of the sequent.
+		 * @param inc Increasement of the sequent.
+		 * @param st_id Start index. The default starts from the first element
+		 * @param size Operating size. The default operates on all elements
+		 * @param space Indexing spacing. you can skip elements when create the sequent. The default is no skipping.
 		 */
 		void sequence(ArrValType st_val, ArrValType inc, size_t st_id = 0, 
 			size_t size = std::numeric_limits<size_t>::max(), size_t space = 0);
diff --git a/lib/io/dsv_io.cpp b/lib/io/dsv_io.cpp
index 44bae89..04e1a81 100644
--- a/lib/io/dsv_io.cpp
+++ b/lib/io/dsv_io.cpp
@@ -456,6 +456,51 @@ void gctl::dsv_io::row_output(std::string name, switch_type_e s)
     return;
 }
 
+void gctl::dsv_io::add_column(std::string name)
+{
+    table_cell empty_cell;
+    for (size_t i = 0; i < table_.size(); i++)
+    {
+        table_[i].push_back(empty_cell);
+    }
+
+    table_[0].back().str_ = name;
+    col_num_++;
+    return;
+}
+
+void gctl::dsv_io::add_column(int idx, std::string name)
+{
+    table_cell empty_cell;
+    if (idx <= 0)
+    {
+        for (size_t i = 0; i < table_.size(); i++)
+        {
+            table_[i].push_back(empty_cell);
+        }
+
+        table_[0].back().str_ = name;
+        col_num_++;
+    }
+    else
+    {
+        for (size_t i = 0; i < table_.size(); i++)
+        {
+            table_[i].insert(table_[i].begin() + idx, empty_cell);
+        }
+
+        table_[0][idx].str_ = name;
+        col_num_++;
+    }
+    return;
+}
+
+void gctl::dsv_io::add_column(std::string id_name, std::string name)
+{
+    add_column(name_index(id_name), name);
+    return;
+}
+
 gctl::geodsv_io::geodsv_io(){}
 
 gctl::geodsv_io::~geodsv_io(){}
@@ -474,7 +519,7 @@ gctl::geodsv_io::geodsv_io(std::string filename, std::string file_exten, table_h
     else load_text(filename, file_exten, t);
 }
 
-void gctl::geodsv_io::fill_column_point2dc(int xid, int yid, const array<point2dc> &data, int p)
+void gctl::geodsv_io::fill_column_point2dc(const array<point2dc> &data, int xid, int yid, int p)
 {
     if (xid > col_num_ || yid > col_num_ || xid == yid || xid <= 0 || yid <= 0)
     {
@@ -498,13 +543,13 @@ void gctl::geodsv_io::fill_column_point2dc(int xid, int yid, const array<point2d
     return;
 }
 
-void gctl::geodsv_io::fill_column_point2dc(std::string xname, std::string yname, const array<point2dc> &data, int p)
+void gctl::geodsv_io::fill_column_point2dc(const array<point2dc> &data, std::string xname, std::string yname, int p)
 {
-    fill_column_point2dc(name_index(xname, false), name_index(yname, false), data, p);
+    fill_column_point2dc(data, name_index(xname, false), name_index(yname, false), p);
     return;
 }
 
-void gctl::geodsv_io::fill_column_point3dc(int xid, int yid, int zid, const array<point3dc> &data, int p)
+void gctl::geodsv_io::fill_column_point3dc(const array<point3dc> &data, int xid, int yid, int zid, int p)
 {
     if (xid > col_num_ || yid > col_num_ || zid > col_num_ || xid == yid || yid == zid || xid == zid
         || xid <= 0 || yid <= 0 || zid <= 0)
@@ -534,13 +579,13 @@ void gctl::geodsv_io::fill_column_point3dc(int xid, int yid, int zid, const arra
     return;
 }
 
-void gctl::geodsv_io::fill_column_point3dc(std::string xname, std::string yname, std::string zname, const array<point3dc> &data, int p)
+void gctl::geodsv_io::fill_column_point3dc(const array<point3dc> &data, std::string xname, std::string yname, std::string zname, int p)
 {
-    fill_column_point3dc(name_index(xname, false), name_index(yname, false), name_index(zname, false), data, p);
+    fill_column_point3dc(data, name_index(xname, false), name_index(yname, false), name_index(zname, false), p);
     return;
 }
 
-void gctl::geodsv_io::get_column_point2dc(int xid, int yid, array<point2dc> &data)
+void gctl::geodsv_io::get_column_point2dc(array<point2dc> &data, int xid, int yid)
 {
     if (xid > col_num_ || yid > col_num_ || xid == yid || xid <= 0 || yid <= 0)
     {
@@ -556,13 +601,13 @@ void gctl::geodsv_io::get_column_point2dc(int xid, int yid, array<point2dc> &dat
     return;
 }
 
-void gctl::geodsv_io::get_column_point2dc(std::string xname, std::string yname, array<point2dc> &data)
+void gctl::geodsv_io::get_column_point2dc(array<point2dc> &data, std::string xname, std::string yname)
 {
-    get_column_point2dc(name_index(xname, false), name_index(yname, false), data);
+    get_column_point2dc(data, name_index(xname, false), name_index(yname, false));
     return;
 }
 
-void gctl::geodsv_io::get_column_point3dc(int xid, int yid, int zid, array<point3dc> &data)
+void gctl::geodsv_io::get_column_point3dc(array<point3dc> &data, int xid, int yid, int zid)
 {
     if (xid > col_num_ || yid > col_num_ || zid > col_num_ || xid == yid || yid == zid || xid == zid
         || xid <= 0 || yid <= 0 || zid <= 0)
@@ -580,8 +625,8 @@ void gctl::geodsv_io::get_column_point3dc(int xid, int yid, int zid, array<point
     return;
 }
 
-void gctl::geodsv_io::get_column_point3dc(std::string xname, std::string yname, std::string zname, array<point3dc> &data)
+void gctl::geodsv_io::get_column_point3dc(array<point3dc> &data, std::string xname, std::string yname, std::string zname)
 {
-    get_column_point3dc(name_index(xname, false), name_index(yname, false), name_index(zname, false), data);
+    get_column_point3dc(data, name_index(xname, false), name_index(yname, false), name_index(zname, false));
     return;
 }
\ No newline at end of file
diff --git a/lib/io/dsv_io.h b/lib/io/dsv_io.h
index 940c26c..0aefa4d 100644
--- a/lib/io/dsv_io.h
+++ b/lib/io/dsv_io.h
@@ -344,6 +344,29 @@ namespace gctl
 		 * @param s 设置输出类型
 		 */
 		void row_output(std::string name, switch_type_e s = Disable);
+		
+		/**
+		 * @brief 在表格末尾添加一个空白列
+		 * 
+		 * @param name 设置列名称
+		 */
+		void add_column(std::string name = "");
+
+		/**
+		 * @brief 在索引为idx的列后添加一个空白列
+		 * 
+		 * @param idx 列索引 小于等于0时将在表尾添加一列
+		 * @param name 设置列名称
+		 */
+		void add_column(int idx, std::string name = "");
+
+		/**
+		 * @brief 在名称为id_name的列后添加一个空白列
+		 * 
+		 * @param id_name 索引列名称
+		 * @param name 设置列名称
+		 */
+		void add_column(std::string id_name, std::string name = "");
 
 		/**
 		 * @brief 填充表格
@@ -370,7 +393,7 @@ namespace gctl
 		 * @param data 列数据
 		 * @param p 浮点类数据保存时的有效数字位数
 		 */
-		template <typename T> void fill_column(int idx, const array<T> &data, int p = 6);
+		template <typename T> void fill_column(const array<T> &data, int idx, int p = 6);
 
 		/**
 		 * @brief 填充列
@@ -380,7 +403,7 @@ namespace gctl
 		 * @param data 列数据
 		 * @param p 浮点类数据保存时的有效数字位数
 		 */
-		template <typename T> void fill_column(std::string name, const array<T> &data, int p = 6);
+		template <typename T> void fill_column(const array<T> &data, std::string name, int p = 6);
 
 		/**
 		 * @brief 填充行
@@ -390,7 +413,7 @@ namespace gctl
 		 * @param data 行数据
 		 * @param p 浮点类数据保存时的有效数字位数
 		 */
-		template <typename T> void fill_row(int idx, const array<T> &data, int p = 6);
+		template <typename T> void fill_row(const array<T> &data, int idx, int p = 6);
 
 		/**
 		 * @brief 填充行
@@ -400,7 +423,7 @@ namespace gctl
 		 * @param data 行数据
 		 * @param p 浮点类数据保存时的有效数字位数
 		 */
-		template <typename T> void fill_row(std::string name, const array<T> &data, int p = 6);
+		template <typename T> void fill_row(const array<T> &data, std::string name, int p = 6);
 
 		/**
 		 * @brief 获取列数据
@@ -409,7 +432,7 @@ namespace gctl
 		 * @param idx 列索引 从1开始
 		 * @param data 列数据
 		 */
-		template <typename T> void get_column(int idx, array<T> &data);
+		template <typename T> void get_column(array<T> &data, int idx);
 
 		/**
 		 * @brief 获取列数据
@@ -418,7 +441,7 @@ namespace gctl
 		 * @param name 列名称
 		 * @param data 列数据
 		 */
-		template <typename T> void get_column(std::string name, array<T> &data);
+		template <typename T> void get_column(array<T> &data, std::string name);
 		
 		/**
 		 * @brief 获取行数据
@@ -427,7 +450,7 @@ namespace gctl
 		 * @param idx 行索引 从1开始
 		 * @param data 行数据
 		 */
-		template <typename T> void get_row(int idx, array<T> &data);
+		template <typename T> void get_row(array<T> &data, int idx);
 
 		/**
 		 * @brief 获取行数据
@@ -436,7 +459,7 @@ namespace gctl
 		 * @param name 行名称
 		 * @param data 行数据
 		 */
-		template <typename T> void get_row(std::string name, array<T> &data);
+		template <typename T> void get_row(array<T> &data, std::string name);
 		
 		/**
 		 * @brief 获取表格单元数据
@@ -457,7 +480,7 @@ namespace gctl
 		 * @param d 数据
 		 * @param p 浮点类数据保存时的有效数字位数
 		 */
-		template <typename T> void cell(int r, int c, T d, int p = 6){table_[r][c].value(d, p); return;}
+		template <typename T> void cell(T d, int r, int c, int p = 6){table_[r][c].value(d, p); return;}
 	};
 
 	template <typename T>
@@ -488,7 +511,7 @@ namespace gctl
 	}
 
 	template <typename T>
-	void dsv_io::fill_column(int idx, const array<T> &data, int p)
+	void dsv_io::fill_column(const array<T> &data, int idx, int p)
 	{
 		if (idx > col_num_ || idx <= 0)
 		{
@@ -503,14 +526,14 @@ namespace gctl
 	}
 
 	template <typename T>
-	void dsv_io::fill_column(std::string name, const array<T> &data, int p)
+	void dsv_io::fill_column(const array<T> &data, std::string name, int p)
 	{
-		fill_column(name_index(name, false), data, p);
+		fill_column(data, name_index(name, false), p);
 		return;
 	}
 
 	template <typename T>
-	void dsv_io::fill_row(int idx, const array<T> &data, int p)
+	void dsv_io::fill_row(const array<T> &data, int idx, int p)
 	{
 		if (idx > row_num_ || idx <= 0)
 		{
@@ -525,14 +548,14 @@ namespace gctl
 	}
 
 	template <typename T>
-	void dsv_io::fill_row(std::string name, const array<T> &data, int p)
+	void dsv_io::fill_row(const array<T> &data, std::string name, int p)
 	{
-		fill_row(name_index(name, true), data, p);
+		fill_row(data, name_index(name, true), p);
 		return;
 	}
 
 	template <typename T>
-	void dsv_io::get_column(int idx, array<T> &data)
+	void dsv_io::get_column(array<T> &data, int idx)
 	{
 		if (idx > col_num_ || idx <= 0)
 		{
@@ -548,14 +571,14 @@ namespace gctl
 	}
 
 	template <typename T>
-	void dsv_io::get_column(std::string name, array<T> &data)
+	void dsv_io::get_column(array<T> &data, std::string name)
 	{
-		get_column(name_index(name, false), data);
+		get_column(data, name_index(name, false));
 		return;
 	}
 
 	template <typename T>
-	void dsv_io::get_row(int idx, array<T> &data)
+	void dsv_io::get_row(array<T> &data, int idx)
 	{
 		if (idx > row_num_ || idx <= 0)
 		{
@@ -571,9 +594,9 @@ namespace gctl
 	}
 
 	template <typename T>
-	void dsv_io::get_row(std::string name, array<T> &data)
+	void dsv_io::get_row(array<T> &data, std::string name)
 	{
-		get_row(name_index(name, true), data);
+		get_row(data, name_index(name, true));
 		return;
 	}
 
@@ -612,7 +635,7 @@ namespace gctl
 		 * @param data 返回的二维坐标数据 
 		 * @param p 填入的浮点数据有效位数（精度）
 		 */
-		void fill_column_point2dc(int xid, int yid, const array<point2dc> &data, int p = 6);
+		void fill_column_point2dc(const array<point2dc> &data, int xid, int yid, int p = 6);
 
 		/**
 		 * @brief 填充二维坐标列
@@ -622,7 +645,7 @@ namespace gctl
 		 * @param data 返回的二维坐标数据 
 		 * @param p 填入的浮点数据有效位数（精度）
 		 */
-		void fill_column_point2dc(std::string xname, std::string yname, const array<point2dc> &data, int p = 6);
+		void fill_column_point2dc(const array<point2dc> &data, std::string xname, std::string yname, int p = 6);
 
 		/**
 		 * @brief 填充三维坐标列
@@ -633,7 +656,7 @@ namespace gctl
 		 * @param data 返回的三维坐标数据 
 		 * @param p 填入的浮点数据有效位数（精度）
 		 */
-		void fill_column_point3dc(int xid, int yid, int zid, const array<point3dc> &data, int p = 6);
+		void fill_column_point3dc(const array<point3dc> &data, int xid, int yid, int zid, int p = 6);
 
 		/**
 		 * @brief 填充三维坐标列
@@ -644,7 +667,7 @@ namespace gctl
 		 * @param data 返回的三维坐标数据 
 		 * @param p 填入的浮点数据有效位数（精度）
 		 */
-		void fill_column_point3dc(std::string xname, std::string yname, std::string zname, const array<point3dc> &data, int p = 6);
+		void fill_column_point3dc(const array<point3dc> &data, std::string xname, std::string yname, std::string zname, int p = 6);
 
 		/**
 		 * @brief 读取二维坐标列
@@ -653,7 +676,7 @@ namespace gctl
 		 * @param yid y坐标列索引 从1开始
 		 * @param data 返回的二维坐标数据 
 		 */
-		void get_column_point2dc(int xid, int yid, array<point2dc> &data);
+		void get_column_point2dc(array<point2dc> &data, int xid, int yid);
 
 		/**
 		 * @brief 读取二维坐标列
@@ -662,7 +685,7 @@ namespace gctl
 		 * @param yname y坐标列名称
 		 * @param data 返回的二维坐标数据 
 		 */
-		void get_column_point2dc(std::string xname, std::string yname, array<point2dc> &data);
+		void get_column_point2dc(array<point2dc> &data, std::string xname, std::string yname);
 
 		/**
 		 * @brief 读取三维坐标列
@@ -672,7 +695,7 @@ namespace gctl
 		 * @param zid z坐标列索引 从1开始
 		 * @param data 返回的三维坐标数据 
 		 */
-		void get_column_point3dc(int xid, int yid, int zid, array<point3dc> &data);
+		void get_column_point3dc(array<point3dc> &data, int xid, int yid, int zid);
 
 		/**
 		 * @brief 读取三维坐标列
@@ -682,7 +705,7 @@ namespace gctl
 		 * @param zname z坐标列名称
 		 * @param data 返回的三维坐标数据 
 		 */
-		void get_column_point3dc(std::string xname, std::string yname, std::string zname, array<point3dc> &data);
+		void get_column_point3dc(array<point3dc> &data, std::string xname, std::string yname, std::string zname);
 	};
 }
 
diff --git a/tool/dsviewer/dsviewer.cpp b/tool/dsviewer/dsviewer.cpp
index 77df11d..0157c98 100644
--- a/tool/dsviewer/dsviewer.cpp
+++ b/tool/dsviewer/dsviewer.cpp
@@ -331,7 +331,7 @@ void statistic(const std::vector<std::string> &cmd_units)
     _1d_array data;
     for (size_t i = 1; i < cmd_units.size(); i++)
     {
-        tc.get_column(cmd_units[i], data);
+        tc.get_column(data, cmd_units[i]);
         std::clog << "column: " << cmd_units[i] 
             << " | " << data.min() << "/" << data.mean() << "/" << data.max() 
             << " | STD: " << data.std() << "\n";