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ee.FeatureCollection.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。
返回指定集合中的第一个条目。
用法 | 返回 |
---|
FeatureCollection.first() | 元素 |
参数 | 类型 | 详细信息 |
---|
此:collection | FeatureCollection | 要从中选择第一个条目的集合。 |
示例
代码编辑器 (JavaScript)
// A global power plant FeatureCollection.
var fc = ee.FeatureCollection('WRI/GPPD/power_plants');
print('The first feature (power plant) in the collection', fc.first());
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)
from pprint import pprint
# A global power plant FeatureCollection.
fc = ee.FeatureCollection('WRI/GPPD/power_plants')
print('The first feature (power plant) in the collection:')
pprint(fc.first().getInfo())
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\u003efirst()\u003c/code\u003e operates on a FeatureCollection and returns the first element within that collection.\u003c/p\u003e\n"],["\u003cp\u003eThis method is useful for quickly accessing and examining a representative entry from a FeatureCollection.\u003c/p\u003e\n"],["\u003cp\u003eExamples demonstrate usage in both JavaScript and Python environments, including Colab with \u003ccode\u003egeemap\u003c/code\u003e.\u003c/p\u003e\n"]]],["The core function retrieves the first element from a `FeatureCollection`. It requires a `FeatureCollection` as input. The function `first()` returns the initial `Element` within the collection. In JavaScript, `fc.first()` accesses the first entry, while in Python, using `pprint(fc.first().getInfo())` provides detailed output. The provided examples utilize a global power plant dataset ('WRI/GPPD/power_plants') to demonstrate how to retrieve the initial feature.\n"],null,["# ee.FeatureCollection.first\n\nReturns the first entry from a given collection.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|-----------------------------|---------|\n| FeatureCollection.first`()` | Element |\n\n| Argument | Type | Details |\n|--------------------|-------------------|------------------------------------------------------|\n| this: `collection` | FeatureCollection | The collection from which to select the first entry. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A global power plant FeatureCollection.\nvar fc = ee.FeatureCollection('WRI/GPPD/power_plants');\n\nprint('The first feature (power plant) in the collection', fc.first());\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\nfrom pprint import pprint\n\n# A global power plant FeatureCollection.\nfc = ee.FeatureCollection('WRI/GPPD/power_plants')\n\nprint('The first feature (power plant) in the collection:')\npprint(fc.first().getInfo())\n```"]]