diff --git a/acp/portal_module.php b/acp/portal_module.php
index 81ed7867..a9f14f29 100644
--- a/acp/portal_module.php
+++ b/acp/portal_module.php
@@ -15,7 +15,7 @@ class portal_module
 	public $new_config = array();
 	protected $c_class;
 	protected $db, $user, $cache, $template, $display_vars, $config, $phpbb_root_path, $phpbb_admin_path, $phpEx, $phpbb_container;
-	protected $root_path, $version_check, $request, $php_ext, $portal_helper, $modules_helper, $log;
+	protected $root_path, $version_check, $request, $php_ext, $portal_helper, $modules_helper, $log, $portal_columns;
 	public $module_column = array();
 
 	public function __construct()
@@ -43,14 +43,10 @@ class portal_module
 		$this->portal_helper = $this->phpbb_container->get('board3.portal.helper');
 		$this->modules_helper = $this->phpbb_container->get('board3.portal.modules_helper');
 		$this->log = $phpbb_log;
+		$this->portal_columns = $this->phpbb_container->get('board3.portal.columns');
 		define('PORTAL_MODULES_TABLE', $this->phpbb_container->getParameter('board3.portal.modules.table'));
 		define('PORTAL_CONFIG_TABLE', $this->phpbb_container->getParameter('board3.portal.config.table'));
 
-		if (!function_exists('column_string_const'))
-		{
-			include($this->root_path . 'includes/functions_modules.' . $this->php_ext);
-		}
-
 		if(!function_exists('obtain_portal_config'))
 		{
 			include($this->root_path . 'includes/functions.' . $this->php_ext);
@@ -120,7 +116,7 @@ class portal_module
 							'MODULE_IMAGE_HEIGHT'	=> $module_data['module_image_height'],
 							'MODULE_IMAGE_SRC'		=> ($module_data['module_image_src']) ? $this->root_path . 'styles/' . $this->user->style['style_path'] . '/theme/images/portal/' . $module_data['module_image_src'] : '',
 							'MODULE_ENABLED'		=> ($module_data['module_status']) ? true : false,
-							'MODULE_SHOW_IMAGE'		=> (in_array(column_num_string($module_data['module_column']), array('center', 'top', 'bottom'))) ? false : true,
+							'MODULE_SHOW_IMAGE'		=> (in_array($this->portal_columns->number_to_string($module_data['module_column']), array('center', 'top', 'bottom'))) ? false : true,
 						));
 
 						if($module_data['module_classname'] != '\board3\portal\modules\custom')
@@ -392,7 +388,7 @@ class portal_module
 				{
 					$installed_modules[] = $cur_module['module_classname'];
 					// Create an array with the columns the module is in
-					$this->module_column[$cur_module['module_classname']][] = column_num_string($cur_module['module_column']);
+					$this->module_column[$cur_module['module_classname']][] = $this->portal_columns->number_to_string($cur_module['module_column']);
 				}
 
 				if ($action == 'move_up')
@@ -418,7 +414,7 @@ class portal_module
 
 				$add_list = $this->request->variable('add', array('' => ''));
 				$add_module = key($add_list);
-				$add_column = $this->request->variable('add_column', column_string_num($add_module));
+				$add_column = $this->request->variable('add_column', $this->portal_columns->string_to_number($add_module));
 				if ($add_column)
 				{
 					$submit = ($this->request->is_set_post('submit')) ? true : false;
@@ -493,7 +489,7 @@ class portal_module
 					// Find new modules
 					foreach ($modules_list as $module_class => $module)
 					{
-						if ($module->get_allowed_columns() & column_string_const($add_module))
+						if ($module->get_allowed_columns() & $this->portal_columns->string_to_constant($add_module))
 						{
 							if ($module->get_language())
 							{
@@ -520,7 +516,7 @@ class portal_module
 					}
 
 					$s_hidden_fields = build_hidden_fields(array(
-						'add_column'	=> column_string_num($add_module),
+						'add_column'	=> $this->portal_columns->string_to_number($add_module),
 					));
 					$this->template->assign_vars(array(
 						'S_MODULE_NAMES'	=> $options,
@@ -563,10 +559,10 @@ class portal_module
 						{
 							$this->user->add_lang_ext('board3/portal', 'modules/' . $this->c_class->get_language());
 						}
-						$template_column = column_num_string($row['module_column']);
+						$template_column = $this->portal_columns->number_to_string($row['module_column']);
 
 						// find out of we can move modules to the left or right
-						if(($this->c_class->get_allowed_columns() & column_string_const(column_num_string($row['module_column'] + 1))) || ($this->c_class->get_allowed_columns() & column_string_const(column_num_string($row['module_column'] + 2)) && $row['module_column'] != 2))
+						if(($this->c_class->get_allowed_columns() & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($row['module_column'] + 1))) || ($this->c_class->get_allowed_columns() & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($row['module_column'] + 2)) && $row['module_column'] != 2))
 						{
 							/**
 							* check if we can actually move
@@ -575,7 +571,7 @@ class portal_module
 							*/
 							if ($row['module_classname'] != '\board3\portal\modules\custom')
 							{
-								$column_string = column_num_string($row['module_column'] + 1); // move 1 right
+								$column_string = $this->portal_columns->number_to_string($row['module_column'] + 1); // move 1 right
 
 								if ($column_string == 'right' && !$this->can_move_module(array('left', 'right'), $row['module_classname']))
 								{
@@ -596,7 +592,7 @@ class portal_module
 							$move_right = false;
 						}
 
-						if(($this->c_class->get_allowed_columns() & column_string_const(column_num_string($row['module_column'] - 1))) || ($this->c_class->get_allowed_columns() & column_string_const(column_num_string($row['module_column'] - 2)) && $row['module_column'] != 2))
+						if(($this->c_class->get_allowed_columns() & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($row['module_column'] - 1))) || ($this->c_class->get_allowed_columns() & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($row['module_column'] - 2)) && $row['module_column'] != 2))
 						{
 							/**
 							* check if we can actually move
@@ -605,7 +601,7 @@ class portal_module
 							*/
 							if ($row['module_classname'] != '\board3\portal\modules\custom')
 							{
-								$column_string = column_num_string($row['module_column'] - 1); // move 1 left
+								$column_string = $this->portal_columns->number_to_string($row['module_column'] - 1); // move 1 left
 
 								if ($column_string == 'left' && !$this->can_move_module(array('left', 'right'), $row['module_classname']))
 								{
@@ -868,13 +864,13 @@ class portal_module
 
 		$move_action = 0;
 
-		if ($module_data !== false && $module_data['module_column'] > column_string_num('left'))
+		if ($module_data !== false && $module_data['module_column'] > $this->portal_columns->string_to_number('left'))
 		{
-			if($this->c_class->columns & column_string_const(column_num_string($module_data['module_column'] - 1)))
+			if($this->c_class->columns & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($module_data['module_column'] - 1)))
 			{
 				$move_action = 1; // we move 1 column to the left
 			}
-			else if($this->c_class->columns & column_string_const(column_num_string($module_data['module_column'] - 2)) && $module_data['module_column'] != 2)
+			else if($this->c_class->columns & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($module_data['module_column'] - 2)) && $module_data['module_column'] != 2)
 			{
 				$move_action = 2; // we move 2 columns to the left
 			}
@@ -892,7 +888,7 @@ class portal_module
 			*/
 			if ($module_data['module_classname'] != '\board3\portal\modules\custom' && $move_action == 1)
 			{
-				$column_string = column_num_string($module_data['module_column'] - $move_action);
+				$column_string = $this->portal_columns->number_to_string($module_data['module_column'] - $move_action);
 				// we can only move left to the left & center column
 				if ($column_string == 'left' && !$this->can_move_module(array('right', 'left'), $module_data['module_classname']))
 				{
@@ -963,13 +959,13 @@ class portal_module
 
 		$move_action = 0;
 
-		if ($module_data !== false && $module_data['module_column'] < column_string_num('right'))
+		if ($module_data !== false && $module_data['module_column'] < $this->portal_columns->string_to_number('right'))
 		{
-			if($this->c_class->columns & column_string_const(column_num_string($module_data['module_column'] + 1)))
+			if($this->c_class->columns & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($module_data['module_column'] + 1)))
 			{
 				$move_action = 1; // we move 1 column to the right
 			}
-			else if($this->c_class->columns & column_string_const(column_num_string($module_data['module_column'] + 2)) && $module_data['module_column'] != 2)
+			else if($this->c_class->columns & $this->portal_columns->string_to_constant($this->portal_columns->number_to_string($module_data['module_column'] + 2)) && $module_data['module_column'] != 2)
 			{
 				$move_action = 2; // we move 2 columns to the right
 			}
@@ -987,7 +983,7 @@ class portal_module
 			*/
 			if ($module_data['module_classname'] != '\board3\portal\modules\custom' && $move_action == 1)
 			{
-				$column_string = column_num_string($module_data['module_column'] + $move_action);
+				$column_string = $this->portal_columns->number_to_string($module_data['module_column'] + $move_action);
 				// we can only move right to the right & center column
 				if ($column_string == 'right' && !$this->can_move_module(array('right', 'left'), $module_data['module_classname']))
 				{
diff --git a/config/services.yml b/config/services.yml
index 1b5c8aaa..568eed95 100644
--- a/config/services.yml
+++ b/config/services.yml
@@ -17,6 +17,7 @@ services:
     board3.portal.main:
         class: board3\portal\controller\main
         arguments:
+            - @board3.portal.columns
             - @config
             - @board3.portal.controller_helper
             - @template
@@ -31,6 +32,7 @@ services:
         class: board3\portal\controller\helper
         arguments:
             - @auth
+            - @board3.portal.columns
             - @config
             - @template
             - @user
@@ -68,6 +70,9 @@ services:
             - @config
             - @request
 
+    board3.portal.columns:
+        class: board3\portal\portal\columns
+
     board3.portal.fetch_posts:
         class: board3\portal\portal\fetch_posts
         arguments:
diff --git a/controller/helper.php b/controller/helper.php
index 44671acf..230fcbcb 100644
--- a/controller/helper.php
+++ b/controller/helper.php
@@ -11,6 +11,9 @@ namespace board3\portal\controller;
 
 class helper
 {
+	/** @var \board3\portal\portal\columns */
+	protected $portal_columns;
+
 	/**
 	* Auth object
 	* @var \phpbb\auth\auth
@@ -76,6 +79,7 @@ class helper
 	* NOTE: The parameters of this method must match in order and type with
 	* the dependencies defined in the services.yml file for this service.
 	* @param \phpbb\auth\auth $auth Auth object
+	* @param \board3\portal\portal\columns $portal_columns Board3 Portal columns object
 	* @param \phpbb\config\config $config phpBB Config object
 	* @param \phpbb\template $template Template object
 	* @param \phpbb\user $user User object
@@ -84,9 +88,10 @@ class helper
 	* @param string $phpbb_root_path phpBB root path
 	* @param string $php_ext PHP file extension
 	*/
-	public function __construct($auth, $config, $template, $user, $path_helper, $portal_helper, $phpbb_root_path, $php_ext)
+	public function __construct($auth, $portal_columns, $config, $template, $user, $path_helper, $portal_helper, $phpbb_root_path, $php_ext)
 	{
 		$this->auth = $auth;
+		$this->portal_columns = $portal_columns;
 		$this->config = $config;
 		$this->template = $template;
 		$this->user = $user;
@@ -161,13 +166,15 @@ class helper
 	*/
 	protected function check_column_disabled($row)
 	{
-		return ($this->config['board3_left_column'] === false && column_num_string($row['module_column']) === 'left') || ($this->config['board3_right_column'] === false && column_num_string($row['module_column']) === 'right');
+		return ($this->config['board3_left_column'] === false && $this->portal_columns->number_to_string($row['module_column']) === 'left') || ($this->config['board3_right_column'] === false && $this->portal_columns->number_to_string($row['module_column']) === 'right');
 	}
 
 	/**
 	* Check if user is in required groups
 	*
 	* @param array $row Module row
+	*
+	* @return bool True if group has access, false if not
 	*/
 	protected function check_group_access($row)
 	{
@@ -215,7 +222,7 @@ class helper
 	{
 		if (is_array($template_module))
 		{
-			$this->template->assign_block_vars('modules_' . column_num_string($row['module_column']), array(
+			$this->template->assign_block_vars('modules_' . $this->portal_columns->number_to_string($row['module_column']), array(
 				'TEMPLATE_FILE'			=> 'portal/modules/' . $template_module['template'],
 				'IMAGE_SRC'			=> $this->path_helper->get_web_root_path() . $this->root_path . 'styles/' . $this->user->style['style_path'] . '/theme/images/portal/' . $template_module['image_src'],
 				'TITLE'				=> $template_module['title'],
@@ -227,7 +234,7 @@ class helper
 		}
 		else
 		{
-			$this->template->assign_block_vars('modules_' . column_num_string($row['module_column']), array(
+			$this->template->assign_block_vars('modules_' . $this->portal_columns->number_to_string($row['module_column']), array(
 				'TEMPLATE_FILE'			=> 'portal/modules/' . $template_module,
 				'IMAGE_SRC'			=> $this->path_helper->get_web_root_path() . $this->root_path . 'styles/' . $this->user->style['style_path'] . '/theme/images/portal/' . $row['module_image_src'],
 				'IMAGE_WIDTH'			=> $row['module_image_width'],
diff --git a/controller/main.php b/controller/main.php
index 61d32abb..155e7637 100644
--- a/controller/main.php
+++ b/controller/main.php
@@ -11,6 +11,9 @@ namespace board3\portal\controller;
 
 class main
 {
+	/** @var \board3\portal\portal\columns */
+	protected $portal_columns;
+
 	/**
 	* phpBB Config object
 	* @var \phpbb\config\config
@@ -81,6 +84,7 @@ class main
 	* Constructor
 	* NOTE: The parameters of this method must match in order and type with
 	* the dependencies defined in the services.yml file for this service.
+	* @param \board3\portal\portal\columns $portal_columns Board3 Portal columns object
 	* @param \phpbb\config\config $config phpBB Config object
 	* @param \board3\portal\controller\helper $controller_helper Controller helper
 	* @param \phpbb\template $template Template object
@@ -91,10 +95,11 @@ class main
 	* @param string $config_table Board3 config table
 	* @param string $modules_table Board3 modules table
 	*/
-	public function __construct($config, $controller_helper, $template, $user, $path_helper, $phpbb_root_path, $php_ext, $config_table, $modules_table)
+	public function __construct($portal_columns, $config, $controller_helper, $template, $user, $path_helper, $phpbb_root_path, $php_ext, $config_table, $modules_table)
 	{
 		global $portal_root_path;
 
+		$this->portal_columns = $portal_columns;
 		$this->config = $config;
 		$this->controller_helper = $controller_helper;
 		$this->template = $template;
@@ -203,7 +208,7 @@ class main
 	public function get_module_template($row, $module)
 	{
 		$template_module = false;
-		$column = column_num_string($row['module_column']);
+		$column = $this->portal_columns->number_to_string($row['module_column']);
 
 		if (in_array($column, array('left', 'right')) && $this->config['board3_' . $column . '_column'])
 		{
diff --git a/includes/functions_modules.php b/includes/functions_modules.php
index 78196106..01bbc513 100644
--- a/includes/functions_modules.php
+++ b/includes/functions_modules.php
@@ -7,59 +7,44 @@
 *
 */
 
+/**
+ * Convert column number to string equivalent
+ *
+ * @param int $column Column number
+ *
+ * @return string String representation of column number; default: ''
+ * @deprecated 2.1.0-RC1 (to be removed: 2.1.0)
+ */
 function column_num_string($column)
 {
-	switch ($column)
-	{
-		case 1:
-			return 'left';
-		case 2:
-			return 'center';
-		case 3:
-			return 'right';
-		case 4:
-			return 'top';
-		case 5:
-			return 'bottom';
-		default:
-			return 0;
-	}
+	$portal_columns = new \board3\portal\portal\columns();
+	return $portal_columns->number_to_string($column);
 }
 
+/**
+ * Convert column string to equivalent number
+ *
+ * @param string $column Column name
+ *
+ * @return int The column number; default: 0
+ * @deprecated 2.1.0-RC1 (to be removed: 2.1.0)
+ */
 function column_string_num($column)
 {
-	switch ($column)
-	{
-		case 'left':
-			return 1;
-		case 'center':
-			return 2;
-		case 'right':
-			return 3;
-		case 'top':
-			return 4;
-		case 'bottom':
-			return 5;
-		default:
-			return 0;
-	}
+	$portal_columns = new \board3\portal\portal\columns();
+	return $portal_columns->string_to_number($column);
 }
 
+/**
+ * Convert column string to equivalent constant
+ *
+ * @param string $column Column name
+ *
+ * @return int Column constant; default: 0
+ * @deprecated 2.1.0-RC1 (to be removed: 2.1.0)
+ */
 function column_string_const($column)
 {
-	switch ($column)
-	{
-		case 'top':
-			return 1;
-		case 'left':
-			return 2;
-		case 'center':
-			return 4;
-		case 'right':
-			return 8;
-		case 'bottom':
-			return 16;
-		default:
-			return 0;
-	}
+	$portal_columns = new \board3\portal\portal\columns();
+	return $portal_columns->string_to_constant($column);
 }
diff --git a/portal/columns.php b/portal/columns.php
new file mode 100644
index 00000000..07380acd
--- /dev/null
+++ b/portal/columns.php
@@ -0,0 +1,91 @@
+<?php
+/**
+ *
+ * @package Board3 Portal v2.1
+ * @copyright (c) 2014 Board3 Group ( www.board3.de )
+ * @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+ *
+ */
+
+namespace board3\portal\portal;
+
+class columns
+{
+	/**
+	 * Convert column number to string equivalent
+	 *
+	 * @param int $column Column number
+	 *
+	 * @return string String representation of column number; default: ''
+	 */
+	public function number_to_string($column)
+	{
+		switch ($column)
+		{
+			case 1:
+				return 'left';
+			case 2:
+				return 'center';
+			case 3:
+				return 'right';
+			case 4:
+				return 'top';
+			case 5:
+				return 'bottom';
+			default:
+				return '';
+		}
+	}
+
+	/**
+	 * Convert column string to equivalent number
+	 *
+	 * @param string $column Column name
+	 *
+	 * @return int The column number; default: 0
+	 */
+	public function string_to_number($column)
+	{
+		switch ($column)
+		{
+			case 'left':
+				return 1;
+			case 'center':
+				return 2;
+			case 'right':
+				return 3;
+			case 'top':
+				return 4;
+			case 'bottom':
+				return 5;
+			default:
+				return 0;
+		}
+	}
+
+	/**
+	 * Convert column string to equivalent constant
+	 *
+	 * @param string $column Column name
+	 *
+	 * @return int Column constant; default: 0
+	 */
+	public function string_to_constant($column)
+	{
+		switch ($column)
+		{
+			case 'top':
+				return 1;
+			case 'left':
+				return 2;
+			case 'center':
+				return 4;
+			case 'right':
+				return 8;
+			case 'bottom':
+				return 16;
+			default:
+				return 0;
+		}
+	}
+}
\ No newline at end of file
diff --git a/tests/unit/acp/move_module_test.php b/tests/unit/acp/move_module_test.php
index b8e13d31..c6d0c04c 100644
--- a/tests/unit/acp/move_module_test.php
+++ b/tests/unit/acp/move_module_test.php
@@ -43,6 +43,8 @@ class phpbb_acp_move_module_test extends \board3\portal\tests\testframework\data
 		$phpbb_container->set('board3.portal.modules_helper', new \board3\portal\includes\modules_helper(new \phpbb\auth\auth(), $config, $request));
 		$phpbb_container->setParameter('board3.portal.modules.table', $table_prefix . 'portal_modules');
 		$phpbb_container->setParameter('board3.portal.config.table', $table_prefix . 'portal_config');
+		$this->portal_columns = new \board3\portal\portal\columns();
+		$phpbb_container->set('board3.portal.columns', $this->portal_columns);
 		$cache = $this->getMock('\phpbb\cache\cache', array('destroy', 'sql_exists', 'get', 'put'));
 		$cache->expects($this->any())
 			->method('destroy')
@@ -72,7 +74,7 @@ class phpbb_acp_move_module_test extends \board3\portal\tests\testframework\data
 		$portal_modules = obtain_portal_modules();
 		foreach($portal_modules as $cur_module)
 		{
-			$this->portal_module->module_column[$cur_module['module_classname']][] = column_num_string($cur_module['module_column']);
+			$this->portal_module->module_column[$cur_module['module_classname']][] = $this->portal_columns->number_to_string($cur_module['module_column']);
 		}
 	}
 
@@ -191,7 +193,7 @@ class phpbb_acp_move_module_test extends \board3\portal\tests\testframework\data
 		if ($add_to_column)
 		{
 			$module_data = $this->portal_module->get_move_module_data($module_id);
-			$this->portal_module->module_column[$module_data['module_classname']][] = column_num_string($add_to_column);
+			$this->portal_module->module_column[$module_data['module_classname']][] = $this->portal_columns->number_to_string($add_to_column);
 		}
 
 		for ($i = 1; $i <= $move_right; $i++)
@@ -242,7 +244,7 @@ class phpbb_acp_move_module_test extends \board3\portal\tests\testframework\data
 		if ($add_to_column)
 		{
 			$module_data = $this->portal_module->get_move_module_data($module_id);
-			$this->portal_module->module_column[$module_data['module_classname']][] = column_num_string($add_to_column);
+			$this->portal_module->module_column[$module_data['module_classname']][] = $this->portal_columns->number_to_string($add_to_column);
 		}
 
 		// We always start in the right column = 3
diff --git a/tests/unit/controller/helper_test.php b/tests/unit/controller/helper_test.php
index d1ba28e7..45419abb 100644
--- a/tests/unit/controller/helper_test.php
+++ b/tests/unit/controller/helper_test.php
@@ -40,6 +40,7 @@ class helper_test extends \board3\portal\tests\testframework\test_case
 		$this->user->data['group_id'] = 2;
 		$this->phpbb_root_path = dirname(__FILE__) . '/../../../../../../';
 		$this->php_ext = 'php';
+		$this->portal_columns = new \board3\portal\portal\columns();
 		$this->modules = array(
 			'\board3\portal\modules\link_us'	=> new \board3\portal\modules\link_us($config, new \board3\portal\tests\mock\template($this), new \board3\portal\tests\mock\user),
 		);
@@ -60,6 +61,7 @@ class helper_test extends \board3\portal\tests\testframework\test_case
 	{
 		$controller_helper = new \board3\portal\controller\helper(
 			$this->auth,
+			$this->portal_columns,
 			$this->config,
 			$this->template,
 			$this->user,
diff --git a/tests/unit/functions/functions_modules_test.php b/tests/unit/functions/functions_modules_test.php
index 4c586095..e6755a33 100644
--- a/tests/unit/functions/functions_modules_test.php
+++ b/tests/unit/functions/functions_modules_test.php
@@ -14,8 +14,8 @@ class phpbb_functions_functions_modules_test extends PHPUnit_Framework_TestCase
 	public function data_column_num_string()
 	{
 		return array(
-			array(0, ''),
-			array(0, false),
+			array('', ''),
+			array('', false),
 			array('left', 1),
 			array('center', 2),
 			array('right', 3),
diff --git a/tests/unit/portal/columns_test.php b/tests/unit/portal/columns_test.php
new file mode 100644
index 00000000..b9ccf553
--- /dev/null
+++ b/tests/unit/portal/columns_test.php
@@ -0,0 +1,67 @@
+<?php
+/**
+ *
+ * @package Board3 Portal Testing
+ * @copyright (c) Board3 Group ( www.board3.de )
+ * @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+ *
+ */
+
+class board3_portal_columns_test extends \board3\portal\tests\testframework\test_case
+{
+	protected $portal_columns;
+
+	public function setUp()
+	{
+		parent::setUp();
+
+		$this->portal_columns = new \board3\portal\portal\columns();
+	}
+	public function data_column_number_string()
+	{
+		return array(
+			array(4, 'top'),
+			array(1, 'left'),
+			array(2, 'center'),
+			array(3, 'right'),
+			array(5, 'bottom'),
+			array(0, ''),
+		);
+	}
+
+	/**
+	 * @dataProvider data_column_number_string
+	 */
+	public function test_number_to_string($number, $string)
+	{
+		$this->assertEquals($string, $this->portal_columns->number_to_string($number));
+	}
+
+	/**
+	 * @dataProvider data_column_number_string
+	 */
+	public function test_string_to_number($number, $string)
+	{
+		$this->assertEquals($number, $this->portal_columns->string_to_number($string));
+	}
+
+	public function data_column_string_constant()
+	{
+		return array(
+			array('top', 1),
+			array('left', 2),
+			array('center', 4),
+			array('right', 8),
+			array('bottom', 16),
+			array('', 0),
+		);
+	}
+
+	/**
+	 * @dataProvider data_column_string_constant
+	 */
+	public function test_string_to_constant($string, $constant)
+	{
+		$this->assertEquals($constant, $this->portal_columns->string_to_constant($string));
+	}
+}
\ No newline at end of file