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ee.Reducer.group
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
按给定输入的值对 reducer 记录进行分组,并使用给定的 reducer 缩减每个组。
用法 | 返回 |
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Reducer.group(groupField, groupName) | 缩减器 |
参数 | 类型 | 详细信息 |
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此:reducer | 缩减器 | 要应用于每个组的缩减器(不含分组字段)。 |
groupField | 整数,默认值:0 | 包含记录组的字段。 |
groupName | 字符串,默认值:“group” | 包含群组的字典键。默认为“group”。 |
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最后更新时间 (UTC):2025-07-26。
[null,null,["最后更新时间 (UTC):2025-07-26。"],[[["\u003cp\u003eGroups records based on a specified field, creating separate groups for each unique value in that field.\u003c/p\u003e\n"],["\u003cp\u003eApplies a given reducer function to each group of records, effectively reducing each group to a single result.\u003c/p\u003e\n"],["\u003cp\u003eAssigns the original reducer to process individual records within each group, excluding the grouping field itself.\u003c/p\u003e\n"],["\u003cp\u003eOrganizes the grouped data within a dictionary-like structure, using 'group' as the default key to access the grouped records.\u003c/p\u003e\n"]]],["The `Reducer.group` function groups records based on a specified `groupField` (defaulting to field 0). It then applies a provided `reducer` to each group, excluding the grouping field. The result of the reducer on each group is stored under a `groupName` key (defaulting to \"group\"). The function itself returns a `Reducer` object. The `groupField` type can be an Integer.\n"],null,["# ee.Reducer.group\n\nGroups reducer records by the value of a given input and reduces each group with the given reducer.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-------------------------------------------------|---------|\n| Reducer.group`(`*groupField* `, `*groupName*`)` | Reducer |\n\n| Argument | Type | Details |\n|-----------------|--------------------------|------------------------------------------------------------------|\n| this: `reducer` | Reducer | The reducer to apply to each group, without the group field. |\n| `groupField` | Integer, default: 0 | The field that contains record groups. |\n| `groupName` | String, default: \"group\" | The dictionary key that contains the group. Defaults to 'group'. |"]]