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[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06 UTC."],[[["\u003cp\u003eComputes the natural logarithm of each element in an input array.\u003c/p\u003e\n"],["\u003cp\u003eReturns an array with the same dimensions as the input array, containing the calculated logarithms.\u003c/p\u003e\n"],["\u003cp\u003eUsage involves calling the \u003ccode\u003e.log()\u003c/code\u003e method on an Earth Engine \u003ccode\u003eArray\u003c/code\u003e object.\u003c/p\u003e\n"]]],["The `Array.log()` function computes the natural logarithm of each element within an input array. It accepts an array as input and returns a new array containing the natural logarithm of each corresponding element. Example usage demonstrates calculating the logarithm of `[e^-1, 1, e]` resulting in `[-1, 0, 1]`. The function's application is further visualized via charts that display the calculated logarithmic values against a range of input values.\n"],null,["On an element-wise basis, computes the natural logarithm of the input.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|---------------|---------|\n| Array.log`()` | Array |\n\n| Argument | Type | Details |\n|---------------|-------|------------------|\n| this: `input` | Array | The input array. |\n\nExamples\n\nCode Editor (JavaScript) \n\n```javascript\nprint(ee.Array([Math.pow(Math.E, -1), 1, Math.E]).log()); // [-1,0,1]\n\nvar start = 0.1;\nvar end = 6;\nvar points = ee.Array(ee.List.sequence(start, end, null, 50));\nvar values = points.log();\n\n// Plot log() defined above.\nvar chart = ui.Chart.array.values(values, 0, points)\n .setOptions({\n viewWindow: {min: start, max: end},\n hAxis: {\n title: 'x',\n viewWindowMode: 'maximized',\n ticks: [\n {v: 0},\n {v: 3},\n {v: end}]\n },\n vAxis: {\n title: 'log(x)',\n ticks: [\n {v: -3},\n {v: 0},\n {v: 3}]\n },\n lineWidth: 1,\n pointSize: 0,\n });\nprint(chart);\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\nColab (Python) \n\n```python\nimport math\nimport altair as alt\nimport pandas as pd\n\ndisplay(ee.Array([pow(math.e, -1), 1, math.e]).log()) # [-1,0,1]\n\nstart = 0.1\nend = 6\npoints = ee.Array(ee.List.sequence(start, end, None, 50))\nvalues = points.log()\n\ndf = pd.DataFrame({'x': points.getInfo(), 'log(x)': values.getInfo()})\n\n# Plot log() defined above.\nalt.Chart(df).mark_line().encode(\n x=alt.X('x', axis=alt.Axis(values=[0, 3, end])),\n y=alt.Y('log(x)', axis=alt.Axis(values=[-3, 0, 3]))\n)\n```"]]