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ee.Array.reduce
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Apply a reducer to an array by collapsing all the input values along each specified axis into a single output value computed by the reducer.
The output always has the same dimensionality as the input, and the individual axes are affected as follows:
The axes specified in the 'axes' parameter have their length reduced to 1 (by applying the reducer).
If the reducer has multiple inputs or multiple outputs, the axis specified in 'fieldAxis' will be used to provide the reducer's inputs and store the reducer's outputs.
All other axes are unaffected (independent reductions are performed).
| Usage | Returns | Array.reduce(reducer, axes, fieldAxis) | Array |
| Argument | Type | Details | this: array | Array | The array. |
reducer | Reducer | The reducer to apply. Each of its outputs must be a number, not an array or other type. |
axes | List | The list of axes over which to reduce. The output will have a length of 1 in all these axes. |
fieldAxis | Integer, default: null | The axis to use as the reducer's input and output fields. Only required if the reducer has multiple inputs or multiple outputs, in which case the axis must have length equal to the number of reducer inputs, and in the result it will have length equal to the number of reducer outputs. |
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Last updated 2024-07-13 UTC.
[null,null,["Last updated 2024-07-13 UTC."],[[["\u003cp\u003e\u003ccode\u003eArray.reduce\u003c/code\u003e collapses input values along specified axes into single output values using a reducer function.\u003c/p\u003e\n"],["\u003cp\u003eThe output array retains the original input dimensionality, with specified axes reduced to length 1.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003efieldAxis\u003c/code\u003e is used when your reducer has multiple inputs or outputs, aligning with those fields.\u003c/p\u003e\n"],["\u003cp\u003eIndependent reductions are performed along all other axes not specified in the \u003ccode\u003eaxes\u003c/code\u003e parameter.\u003c/p\u003e\n"]]],[],null,["# ee.Array.reduce\n\nApply a reducer to an array by collapsing all the input values along each specified axis into a single output value computed by the reducer.\n\n\u003cbr /\u003e\n\nThe output always has the same dimensionality as the input, and the individual axes are affected as follows:\n\n- The axes specified in the 'axes' parameter have their length reduced to 1 (by applying the reducer).\n\n- If the reducer has multiple inputs or multiple outputs, the axis specified in 'fieldAxis' will be used to provide the reducer's inputs and store the reducer's outputs.\n\n- All other axes are unaffected (independent reductions are performed).\n\n| Usage | Returns |\n|----------------------------------------------|---------|\n| Array.reduce`(reducer, axes, `*fieldAxis*`)` | Array |\n\n| Argument | Type | Details |\n|---------------|------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `array` | Array | The array. |\n| `reducer` | Reducer | The reducer to apply. Each of its outputs must be a number, not an array or other type. |\n| `axes` | List | The list of axes over which to reduce. The output will have a length of 1 in all these axes. |\n| `fieldAxis` | Integer, default: null | The axis to use as the reducer's input and output fields. Only required if the reducer has multiple inputs or multiple outputs, in which case the axis must have length equal to the number of reducer inputs, and in the result it will have length equal to the number of reducer outputs. |"]]