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ee.FeatureCollection.aggregate_first
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。
对集合中对象的指定属性进行聚合，计算集合中第一个对象的属性值。
| 用法 | 返回 |
|---|
FeatureCollection.aggregate_first(property) | |
| 参数 | 类型 | 详细信息 |
|---|
此：collection | FeatureCollection | 要汇总的集合。 |
property | 字符串 | 要从集合的每个元素中使用的属性。 |
示例
代码编辑器 (JavaScript)
// FeatureCollection of power plants in Belgium.
var fc = ee.FeatureCollection('WRI/GPPD/power_plants')
.filter('country_lg == "Belgium"');
print('Fuel source for first power plant in the collection',
fc.aggregate_first('fuel1')); // Wind
Python 设置
如需了解 Python API 和如何使用 geemap 进行交互式开发，请参阅
Python 环境页面。
import ee
import geemap.core as geemap
Colab (Python)
# FeatureCollection of power plants in Belgium.
fc = ee.FeatureCollection('WRI/GPPD/power_plants').filter(
'country_lg == "Belgium"')
print('Fuel source for first power plant in the collection:',
fc.aggregate_first('fuel1').getInfo()) # Wind
如未另行说明，那么本页面中的内容已根据知识共享署名 4.0 许可获得了许可，并且代码示例已根据 Apache 2.0 许可获得了许可。有关详情，请参阅 Google 开发者网站政策。Java 是 Oracle 和/或其关联公司的注册商标。
最后更新时间 (UTC)：2025-07-26。
[null,null,["最后更新时间 (UTC)：2025-07-26。"],[[["\u003cp\u003e\u003ccode\u003eaggregate_first()\u003c/code\u003e calculates and returns the value of a specified property from the first feature within a FeatureCollection.\u003c/p\u003e\n"],["\u003cp\u003eThis function is helpful for quickly accessing the property value of an initial element in a collection without iterating through all features.\u003c/p\u003e\n"],["\u003cp\u003eUsage involves specifying the property name as an argument to the \u003ccode\u003eaggregate_first()\u003c/code\u003e function, applied to a FeatureCollection.\u003c/p\u003e\n"]]],[],null,["# ee.FeatureCollection.aggregate_first\n\nAggregates over a given property of the objects in a collection, calculating the property value of the first object in the collection.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-----------------------------------------------|---------|\n| FeatureCollection.aggregate_first`(property)` | |\n\n| Argument | Type | Details |\n|--------------------|-------------------|----------------------------------------------------------|\n| this: `collection` | FeatureCollection | The collection to aggregate over. |\n| `property` | String | The property to use from each element of the collection. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// FeatureCollection of power plants in Belgium.\nvar fc = ee.FeatureCollection('WRI/GPPD/power_plants')\n .filter('country_lg == \"Belgium\"');\n\nprint('Fuel source for first power plant in the collection',\n fc.aggregate_first('fuel1')); // Wind\n```\nPython setup\n\nSee the [Python Environment](/earth-engine/guides/python_install) page for information on the Python API and using\n`geemap` for interactive development. \n\n```python\nimport ee\nimport geemap.core as geemap\n```\n\n### Colab (Python)\n\n```python\n# FeatureCollection of power plants in Belgium.\nfc = ee.FeatureCollection('WRI/GPPD/power_plants').filter(\n 'country_lg == \"Belgium\"')\n\nprint('Fuel source for first power plant in the collection:',\n fc.aggregate_first('fuel1').getInfo()) # Wind\n```"]]
