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ee.Array.accum
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Accumulates elements of an array along the given axis, by setting each element of the result to the reduction of elements along that axis up to and including the current position. May be used to make a cumulative sum, a monotonically increasing sequence, etc.
| Usage | Returns | Array.accum(axis, reducer) | Array |
| Argument | Type | Details | this: array | Array | Array to accumulate. |
axis | Integer | Axis along which to perform the accumulation. |
reducer | Reducer, default: null | Reducer to accumulate values. Default is SUM, to produce the cumulative sum of each vector along the given axis. |
Examples
Code Editor (JavaScript)
print(ee.Array([-1]).accum(0)); // [-1]
print(ee.Array([-2, 1]).accum(0)); // [-2, -1]
print(ee.Array([-2, 1, 9]).accum(0)); // [-2, -1, 8]
// accum over 2D arrays with different axes.
print(ee.Array([[1, 3], [5, 7]]).accum(0)); // [[1,3],[6,10]]
print(ee.Array([[1, 3], [5, 7]]).accum(1)); // [[1,4],[5,12]]
// sum is the default reducer.
print(ee.Array([2, -2, 3, 1]).accum(0)); // [2,0,3,4]
print(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.sum())); // [2,0,3,4]
// Some example reducers.
print(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.max())); // [2,2,3,3]
print(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.mean())); // [2,0,1,1]
print(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.min())); // [2,-2,-2,-2]
print(ee.Array([2, -2, 3]).accum(0, ee.Reducer.product())); // [2,-4,-12]
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)
display(ee.Array([-1]).accum(0)) # [-1]
display(ee.Array([-2, 1]).accum(0)) # [-2, -1]
display(ee.Array([-2, 1, 9]).accum(0)) # [-2, -1, 8]
# accum over 2D arrays with different axes.
display(ee.Array([[1, 3], [5, 7]]).accum(0)) # [[1, 3],[6, 10]]
display(ee.Array([[1, 3], [5, 7]]).accum(1)) # [[1, 4],[5, 12]]
# sum is the default reducer.
display(ee.Array([2, -2, 3, 1]).accum(0)) # [2, 0, 3, 4]
# [2, 0, 3, 4]
display(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.sum()))
# Some example reducers.
# [2, 2, 3, 3]
display(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.max()))
# [2, 0, 1, 1]
display(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.mean()))
# [2, -2, -2, -2]
display(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.min()))
# [2, -4, -12]
display(ee.Array([2, -2, 3]).accum(0, ee.Reducer.product()))
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Last updated 2023-10-06 UTC.
[null,null,["Last updated 2023-10-06 UTC."],[[["\u003cp\u003e\u003ccode\u003eArray.accum\u003c/code\u003e calculates the cumulative reduction of elements in an array along a specified axis.\u003c/p\u003e\n"],["\u003cp\u003eIt uses a reducer function, defaulting to sum, to determine how elements are accumulated.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eaxis\u003c/code\u003e argument defines the direction of accumulation (0 for rows, 1 for columns in 2D arrays).\u003c/p\u003e\n"],["\u003cp\u003eVarious reducers like \u003ccode\u003emin\u003c/code\u003e, \u003ccode\u003emax\u003c/code\u003e, \u003ccode\u003emean\u003c/code\u003e, and \u003ccode\u003eproduct\u003c/code\u003e can be used for different cumulative calculations.\u003c/p\u003e\n"],["\u003cp\u003eThe result is a new array with the same dimensions as the input, containing the accumulated values.\u003c/p\u003e\n"]]],[],null,["# ee.Array.accum\n\nAccumulates elements of an array along the given axis, by setting each element of the result to the reduction of elements along that axis up to and including the current position. May be used to make a cumulative sum, a monotonically increasing sequence, etc.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|----------------------------------|---------|\n| Array.accum`(axis, `*reducer*`)` | Array |\n\n| Argument | Type | Details |\n|---------------|------------------------|------------------------------------------------------------------------------------------------------------------|\n| this: `array` | Array | Array to accumulate. |\n| `axis` | Integer | Axis along which to perform the accumulation. |\n| `reducer` | Reducer, default: null | Reducer to accumulate values. Default is SUM, to produce the cumulative sum of each vector along the given axis. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\nprint(ee.Array([-1]).accum(0)); // [-1]\nprint(ee.Array([-2, 1]).accum(0)); // [-2, -1]\nprint(ee.Array([-2, 1, 9]).accum(0)); // [-2, -1, 8]\n\n// accum over 2D arrays with different axes.\nprint(ee.Array([[1, 3], [5, 7]]).accum(0)); // [[1,3],[6,10]]\nprint(ee.Array([[1, 3], [5, 7]]).accum(1)); // [[1,4],[5,12]]\n\n// sum is the default reducer.\nprint(ee.Array([2, -2, 3, 1]).accum(0)); // [2,0,3,4]\nprint(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.sum())); // [2,0,3,4]\n\n// Some example reducers.\nprint(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.max())); // [2,2,3,3]\nprint(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.mean())); // [2,0,1,1]\nprint(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.min())); // [2,-2,-2,-2]\nprint(ee.Array([2, -2, 3]).accum(0, ee.Reducer.product())); // [2,-4,-12]\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\ndisplay(ee.Array([-1]).accum(0)) # [-1]\ndisplay(ee.Array([-2, 1]).accum(0)) # [-2, -1]\ndisplay(ee.Array([-2, 1, 9]).accum(0)) # [-2, -1, 8]\n\n# accum over 2D arrays with different axes.\ndisplay(ee.Array([[1, 3], [5, 7]]).accum(0)) # [[1, 3],[6, 10]]\ndisplay(ee.Array([[1, 3], [5, 7]]).accum(1)) # [[1, 4],[5, 12]]\n\n# sum is the default reducer.\ndisplay(ee.Array([2, -2, 3, 1]).accum(0)) # [2, 0, 3, 4]\n\n# [2, 0, 3, 4]\ndisplay(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.sum()))\n\n\n# Some example reducers.\n# [2, 2, 3, 3]\ndisplay(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.max()))\n\n\n# [2, 0, 1, 1]\ndisplay(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.mean()))\n\n# [2, -2, -2, -2]\ndisplay(ee.Array([2, -2, 3, 1]).accum(0, ee.Reducer.min()))\n\n# [2, -4, -12]\ndisplay(ee.Array([2, -2, 3]).accum(0, ee.Reducer.product()))\n```"]]