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ee.Dictionary.select
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Returns a dictionary with only the specified keys.
| Usage | Returns | Dictionary.select(selectors, ignoreMissing) | Dictionary |
| Argument | Type | Details | this: dictionary | Dictionary | |
selectors | List | A list of keys or regular expressions to select. |
ignoreMissing | Boolean, default: false | Ignore selectors that don't match at least 1 key. |
Examples
Code Editor (JavaScript)
// A dictionary (e.g. results of ee.Image.reduceRegion of an S2 image).
var dict = ee.Dictionary({
B1: 182,
B2: 219,
B3: 443
});
print('Select keys by name', dict.select(['B1', 'B2']));
print('Select keys by regex', dict.select(['B[1-2]']));
print('Set ignoreMissing as true to avoid an unmatched key error',
dict.select({selectors: ['B1', 'B2', 'Region'], ignoreMissing: true}));
Python setup
See the
Python Environment page for information on the Python API and using
geemap for interactive development.
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
})
print('Select keys by name:', dic.select(['B1', 'B2']).getInfo())
print('Select keys by regex:', dic.select(['B[1-2]']).getInfo())
dic_select = dic.select(**{'selectors': ['B1', 'B2', 'Region'],
'ignoreMissing': True})
print('Set ignoreMissing as true to avoid an unmatched key error:',
dic_select.getInfo())
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003e\u003ccode\u003eDictionary.select()\u003c/code\u003e returns a new dictionary containing only the specified keys from the original dictionary.\u003c/p\u003e\n"],["\u003cp\u003eKeys can be selected by providing a list of key names or regular expressions.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eignoreMissing\u003c/code\u003e parameter, when set to true, prevents errors if a selector doesn't match any key in the dictionary.\u003c/p\u003e\n"]]],[],null,["# ee.Dictionary.select\n\nReturns a dictionary with only the specified keys.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------------------------------------------|------------|\n| Dictionary.select`(selectors, `*ignoreMissing*`)` | Dictionary |\n\n| Argument | Type | Details |\n|--------------------|-------------------------|---------------------------------------------------|\n| this: `dictionary` | Dictionary | |\n| `selectors` | List | A list of keys or regular expressions to select. |\n| `ignoreMissing` | Boolean, default: false | Ignore selectors that don't match at least 1 key. |\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\nprint('Select keys by name', dict.select(['B1', 'B2']));\nprint('Select keys by regex', dict.select(['B[1-2]']));\nprint('Set ignoreMissing as true to avoid an unmatched key error',\n dict.select({selectors: ['B1', 'B2', 'Region'], ignoreMissing: true}));\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\nprint('Select keys by name:', dic.select(['B1', 'B2']).getInfo())\nprint('Select keys by regex:', dic.select(['B[1-2]']).getInfo())\n\ndic_select = dic.select(**{'selectors': ['B1', 'B2', 'Region'],\n 'ignoreMissing': True})\nprint('Set ignoreMissing as true to avoid an unmatched key error:',\n dic_select.getInfo())\n```"]]