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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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2023-10-06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\u003eGenerates a chart displaying the frequency distribution of pixel values within a specified image region.\u003c/p\u003e\n"],["\u003cp\u003eThe chart plots histograms for each band of the image, showing the number of pixels with values falling within specific ranges (buckets).\u003c/p\u003e\n"],["\u003cp\u003eUsers can customize the chart by defining the region, scale, and bucket parameters, as well as the maximum number of input values and pixels used in the calculation.\u003c/p\u003e\n"],["\u003cp\u003eThe chart is rendered with customizable axes, titles, and color options for each band.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eui.Chart.image.histogram()\u003c/code\u003e returns a \u003ccode\u003eui.Chart\u003c/code\u003e object, allowing for further manipulation and display within the Earth Engine Code Editor.\u003c/p\u003e\n"]]],["This code generates a histogram chart from an image, plotting band values against their frequency. It utilizes `ui.Chart.image.histogram` with arguments like `image`, `region`, and `scale` to define the data and spatial parameters. Optional settings include `maxBuckets`, `minBucketWidth`, `maxRaw`, and `maxPixels`. The x-axis represents histogram buckets (band value), while the y-axis shows frequency (pixel count). The example demonstrates its application with MODIS surface reflectance data, defining a region and customizing chart appearance.\n"],null,["\u003cbr /\u003e\n\nGenerates a Chart from an image. Computes and plots histograms of the values of the bands in the specified region of the image.\n\n\u003cbr /\u003e\n\n- X-axis: Histogram buckets (of band value).\n\n- Y-axis: Frequency (number of pixels with a band value in the bucket).\n\nReturns a chart.\n\n| Usage | Returns |\n|------------------------------------------------------------------------------------------------------------------------------|----------|\n| `ui.Chart.image.histogram(image, `*region* `, `*scale* `, `*maxBuckets* `, `*minBucketWidth* `, `*maxRaw* `, `*maxPixels*`)` | ui.Chart |\n\n| Argument | Type | Details |\n|------------------|------------------------------------------------|-----------------------------------------------------------------------------------------------------------|\n| `image` | Image | The image to generate a histogram from. |\n| `region` | Feature\\|FeatureCollection\\|Geometry, optional | The region to reduce. If omitted, uses the entire image. |\n| `scale` | Number, optional | The pixel scale used when applying the histogram reducer, in meters. |\n| `maxBuckets` | Number, optional | The maximum number of buckets to use when building a histogram; will be rounded up to a power of 2. |\n| `minBucketWidth` | Number, optional | The minimum histogram bucket width, or null to allow any power of 2. |\n| `maxRaw` | Number, optional | The number of values to accumulate before building the initial histogram. |\n| `maxPixels` | Number, optional | If specified, overrides the maximum number of pixels allowed in the histogram reduction. Defaults to 1e6. |\n\nExamples\n\nCode Editor (JavaScript) \n\n```javascript\n// Define a MODIS surface reflectance composite.\nvar modisSr = ee.ImageCollection('MODIS/006/MOD09A1')\n .filter(ee.Filter.date('2018-06-01', '2018-09-01'))\n .select(['sur_refl_b01', 'sur_refl_b02', 'sur_refl_b06'])\n .mean();\n\n// Define a region to calculate histogram for.\nvar histRegion = ee.Geometry.Rectangle([-112.60, 40.60, -111.18, 41.22]);\n\n// Define the chart and print it to the console.\nvar chart =\n ui.Chart.image.histogram({image: modisSr, region: histRegion, scale: 500})\n .setSeriesNames(['Red', 'NIR', 'SWIR'])\n .setOptions({\n title: 'MODIS SR Reflectance Histogram',\n hAxis: {\n title: 'Reflectance (scaled by 1e4)',\n titleTextStyle: {italic: false, bold: true},\n },\n vAxis:\n {title: 'Count', titleTextStyle: {italic: false, bold: true}},\n colors: ['cf513e', '1d6b99', 'f0af07']\n });\nprint(chart);\n```"]]