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ee.Dictionary.toImage
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。
根据字典中的值创建常量映像。图像的波段会根据 names 实参进行排序和命名。如果未指定任何名称,则按字母数字顺序对频段进行排序。
用法 | 返回 |
---|
Dictionary.toImage(names) | 图片 |
参数 | 类型 | 详细信息 |
---|
此:dictionary | 字典 | 要转换的字典。 |
names | 列表,默认值:null | 输出波段的顺序。 |
示例
代码编辑器 (JavaScript)
// A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).
var dict = ee.Dictionary({
B1: 182,
B2: 219,
B3: 443
});
var selectedKeysImg = dict.toImage(['B1', 'B2']);
print('Selected keys image band names', selectedKeysImg.bandNames());
var allKeysImg = dict.toImage();
print('All keys image band names', allKeysImg.bandNames());
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)
# A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).
dic = ee.Dictionary({
'B1': 182,
'B2': 219,
'B3': 443
})
selected_keys_img = dic.toImage(['B1', 'B2'])
print('Selected keys image band names:',
selected_keys_img.bandNames().getInfo())
all_keys_img = dic.toImage()
print('All keys image band names:', all_keys_img.bandNames().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\u003eThe \u003ccode\u003eDictionary.toImage()\u003c/code\u003e function transforms a dictionary of values into an image where each key represents a band.\u003c/p\u003e\n"],["\u003cp\u003eBand order in the output image can be customized using the optional \u003ccode\u003enames\u003c/code\u003e argument, otherwise, keys are sorted alphanumerically.\u003c/p\u003e\n"],["\u003cp\u003eThis function is useful for visualizing dictionary data, such as results from \u003ccode\u003eee.Image.reduceRegion\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eUsage involves calling \u003ccode\u003etoImage()\u003c/code\u003e on a dictionary object, optionally providing a list of band names for desired ordering.\u003c/p\u003e\n"]]],[],null,["# ee.Dictionary.toImage\n\nCreates an image of constants from values in a dictionary. The bands of the image are ordered and named according to the names argument. If no names are specified, the bands are sorted alpha-numerically.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------------------------|---------|\n| Dictionary.toImage`(`*names*`)` | Image |\n\n| Argument | Type | Details |\n|--------------------|---------------------|--------------------------------|\n| this: `dictionary` | Dictionary | The dictionary to convert. |\n| `names` | List, default: null | The order of the output bands. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).\nvar dict = ee.Dictionary({\n B1: 182,\n B2: 219,\n B3: 443\n});\n\nvar selectedKeysImg = dict.toImage(['B1', 'B2']);\nprint('Selected keys image band names', selectedKeysImg.bandNames());\n\nvar allKeysImg = dict.toImage();\nprint('All keys image band names', allKeysImg.bandNames());\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# A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).\ndic = ee.Dictionary({\n 'B1': 182,\n 'B2': 219,\n 'B3': 443\n})\n\nselected_keys_img = dic.toImage(['B1', 'B2'])\nprint('Selected keys image band names:',\n selected_keys_img.bandNames().getInfo())\n\nall_keys_img = dic.toImage()\nprint('All keys image band names:', all_keys_img.bandNames().getInfo())\n```"]]