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ee.Date.difference
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。
返回两个日期之间的差异（以指定单位表示）；结果为浮点值，基于相应单位的平均长度。
| 用法 | 返回 |
|---|
Date.difference(start, unit) | 浮点数 |
| 参数 | 类型 | 详细信息 |
|---|
this：date | 日期 | |
start | 日期 | |
unit | 字符串 | 可以选择“年”“月”“周”“日”“小时”“分钟”或“秒”。 |
示例
Code Editor (JavaScript)
// Demonstrates the ee.Date.difference method.
var DATE_1 = ee.Date('2020-01-01');
var DATE_2 = ee.Date('2020-01-15');
var diff_1 = DATE_2.difference(DATE_1, 'days');
var diff_2 = DATE_1.difference(DATE_2, 'weeks');
print('The difference between ',
DATE_2,
' relative to ',
DATE_1,
' is ',
diff_1,
' days.');
print('The difference between ',
DATE_1,
' relative to ',
DATE_2,
' is ',
diff_2,
' weeks.');
Python 设置
如需了解 Python API 以及如何使用 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)
DATE_1 = ee.Date('2020-01-01')
DATE_2 = ee.Date('2020-01-15')
# Format the dates as strings.
t1 = DATE_1.format('YYYY-MM-DD').getInfo()
t2 = DATE_2.format('YYYY-MM-DD').getInfo()
# Calculate the differences between dates.
diff_1 = DATE_2.difference(DATE_1, 'days').getInfo()
diff_2 = DATE_1.difference(DATE_2, 'weeks').getInfo()
print(f'The difference between {t2} relative to {t1} is {diff_1} days.')
print(f'The difference between {t1} relative to {t2} is {diff_2} weeks.')
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最后更新时间 (UTC)：2025-07-25。
[null,null,["最后更新时间 (UTC)：2025-07-25。"],[[["\u003cp\u003e\u003ccode\u003eDate.difference()\u003c/code\u003e calculates the difference between two dates, returning a floating-point number.\u003c/p\u003e\n"],["\u003cp\u003eThe difference is calculated based on the average length of the specified unit (e.g., 'year', 'month', 'week', 'day', 'hour', 'minute', or 'second').\u003c/p\u003e\n"],["\u003cp\u003eThe function takes two \u003ccode\u003eee.Date\u003c/code\u003e objects as input, representing the start and end points for the calculation.\u003c/p\u003e\n"],["\u003cp\u003eThe result is relative to the first date and can be positive or negative depending on the order of the dates.\u003c/p\u003e\n"]]],["`Date.difference` calculates the difference between two dates, returning a floating-point number based on the average length of the specified unit. The function takes a `start` date and a `unit` string ('year', 'month', 'week', 'day', 'hour', 'minute', or 'second') as arguments. The output represents the difference in the chosen unit. Examples show calculating differences in days and weeks between two dates, showcasing both JavaScript and Python implementations.\n"],null,["# ee.Date.difference\n\nReturns the difference between two Dates in the specified units; the result is floating-point and based on the average length of the unit.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|--------------------------------|---------|\n| Date.difference`(start, unit)` | Float |\n\n| Argument | Type | Details |\n|--------------|--------|-----------------------------------------------------------------------|\n| this: `date` | Date | |\n| `start` | Date | |\n| `unit` | String | One of 'year', 'month', 'week', 'day', 'hour', 'minute', or 'second'. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// Demonstrates the ee.Date.difference method.\n\nvar DATE_1 = ee.Date('2020-01-01');\nvar DATE_2 = ee.Date('2020-01-15');\n\nvar diff_1 = DATE_2.difference(DATE_1, 'days');\nvar diff_2 = DATE_1.difference(DATE_2, 'weeks');\n\nprint('The difference between ',\n DATE_2,\n ' relative to ',\n DATE_1,\n ' is ',\n diff_1,\n ' days.');\n\nprint('The difference between ',\n DATE_1,\n ' relative to ',\n DATE_2,\n ' is ',\n diff_2,\n ' weeks.');\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\nDATE_1 = ee.Date('2020-01-01')\nDATE_2 = ee.Date('2020-01-15')\n\n# Format the dates as strings.\nt1 = DATE_1.format('YYYY-MM-DD').getInfo()\nt2 = DATE_2.format('YYYY-MM-DD').getInfo()\n\n# Calculate the differences between dates.\ndiff_1 = DATE_2.difference(DATE_1, 'days').getInfo()\ndiff_2 = DATE_1.difference(DATE_2, 'weeks').getInfo()\n\nprint(f'The difference between {t2} relative to {t1} is {diff_1} days.')\nprint(f'The difference between {t1} relative to {t2} is {diff_2} weeks.')\n```"]]
