联合
===============


1.描述
------------

输入要素和更新要素中不叠置的要素或要素的各部分将被写入到输出要素类

2.使用限制
----------------

3.算子id
----------------
igis.gis.analysis.overlay.union

4.参数列表
---------------

+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
| 参数类型 | 参数名称          | 参数关键字       | 必要性 | 参数说明                                                                        | 数据类型 |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
| 输入参数 | url               | 数据源地址       | Y      | 数据源地址                                                                      | String   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
|          | in_features       | 输入要素类或图层 | Y      | 待相交分析图层                                                                  | String   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
|          | join_attributes   | 连接属性         | N      | 确定将输入要素的哪些属性传递到输出要素类                                        | String   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
|          | cluster_tolerance | 容差             | N      | 所有要素坐标（节点和折点）之间的最小距离以及坐标可以沿 X 和/或 Y 方向移动的距离 | Double   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
|          | gaps              | 间隙             | N      | 间隙是输出要素类中被其他面完全包围的区域                                        | String   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+
| 输出参数 | out_feature_class | 结果图层         | Y      | 所创建的要素类，并且结果将写入其中。                                            | String   |
+----------+-------------------+------------------+--------+---------------------------------------------------------------------------------+----------+


5.配置面板
--------------------

.. image:: ../../../_static/images/union_panel.jpg
   :width: 300px


6.调用示例
------------------
.. code::
  
    {
      "params":{
        "url":"kudu://172.20.20.15:7051/geomesa_spark",
        "in_features":"hainan_select_460201100，hainan_select_460201451",
        "cluster_tolerance":"0.001",
        "out_feature_class":"hainan_union"
      },
      "identifier":"igis.gis.analysis.overlay.union"
    }