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إثبات أهلية جميع المشاريع غير التجارية المسجّلة لاستخدام Earth Engine قبل
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ee.Classifier.explain
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الاستخدام | المرتجعات |
---|
Classifier.explain() | القاموس |
الوسيطة | النوع | التفاصيل |
---|
هذا: classifier | المصنِّف | تمثّل هذه السمة المصنِّف المطلوب وصفه. |
أمثلة
محرّر الرموز البرمجية (JavaScript)
// A Sentinel-2 surface reflectance image, reflectance bands selected,
// serves as the source for training and prediction in this contrived example.
var img = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG')
.select('B.*');
// ESA WorldCover land cover map, used as label source in classifier training.
var lc = ee.Image('ESA/WorldCover/v100/2020');
// Remap the land cover class values to a 0-based sequential series.
var classValues = [10, 20, 30, 40, 50, 60, 70, 80, 90, 95, 100];
var remapValues = ee.List.sequence(0, 10);
var label = 'lc';
lc = lc.remap(classValues, remapValues).rename(label).toByte();
// Add land cover as a band of the reflectance image and sample 100 pixels at
// 10 m scale from each land cover class within a region of interest.
var roi = ee.Geometry.Rectangle(-122.347, 37.743, -122.024, 37.838);
var sample = img.addBands(lc).stratifiedSample({
numPoints: 100,
classBand: label,
region: roi,
scale: 10,
geometries: true
});
// Add a random value field to the sample and use it to approximately split 80%
// of the features into a training set and 20% into a validation set.
sample = sample.randomColumn();
var trainingSample = sample.filter('random <= 0.8');
var validationSample = sample.filter('random > 0.8');
// Train a 10-tree random forest classifier from the training sample.
var trainedClassifier = ee.Classifier.smileRandomForest(10).train({
features: trainingSample,
classProperty: label,
inputProperties: img.bandNames()
});
// Get information about the trained classifier.
print('Results of trained classifier', trainedClassifier.explain());
// Get a confusion matrix and overall accuracy for the training sample.
var trainAccuracy = trainedClassifier.confusionMatrix();
print('Training error matrix', trainAccuracy);
print('Training overall accuracy', trainAccuracy.accuracy());
// Get a confusion matrix and overall accuracy for the validation sample.
validationSample = validationSample.classify(trainedClassifier);
var validationAccuracy = validationSample.errorMatrix(label, 'classification');
print('Validation error matrix', validationAccuracy);
print('Validation accuracy', validationAccuracy.accuracy());
// Classify the reflectance image from the trained classifier.
var imgClassified = img.classify(trainedClassifier);
// Add the layers to the map.
var classVis = {
min: 0,
max: 10,
palette: ['006400' ,'ffbb22', 'ffff4c', 'f096ff', 'fa0000', 'b4b4b4',
'f0f0f0', '0064c8', '0096a0', '00cf75', 'fae6a0']
};
Map.setCenter(-122.184, 37.796, 12);
Map.addLayer(img, {bands: ['B11', 'B8', 'B3'], min: 100, max: 3500}, 'img');
Map.addLayer(lc, classVis, 'lc');
Map.addLayer(imgClassified, classVis, 'Classified');
Map.addLayer(roi, {color: 'white'}, 'ROI', false, 0.5);
Map.addLayer(trainingSample, {color: 'black'}, 'Training sample', false);
Map.addLayer(validationSample, {color: 'white'}, 'Validation sample', false);
إعداد Python
راجِع صفحة
بيئة Python للحصول على معلومات حول واجهة برمجة التطبيقات Python واستخدام
geemap
للتطوير التفاعلي.
import ee
import geemap.core as geemap
Colab (Python)
# A Sentinel-2 surface reflectance image, reflectance bands selected,
# serves as the source for training and prediction in this contrived example.
img = ee.Image(
'COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG'
).select('B.*')
# ESA WorldCover land cover map, used as label source in classifier training.
lc = ee.Image('ESA/WorldCover/v100/2020')
# Remap the land cover class values to a 0-based sequential series.
class_values = [10, 20, 30, 40, 50, 60, 70, 80, 90, 95, 100]
remap_values = ee.List.sequence(0, 10)
label = 'lc'
lc = lc.remap(class_values, remap_values).rename(label).toByte()
# Add land cover as a band of the reflectance image and sample 100 pixels at
# 10 m scale from each land cover class within a region of interest.
roi = ee.Geometry.Rectangle(-122.347, 37.743, -122.024, 37.838)
sample = img.addBands(lc).stratifiedSample(
numPoints=100, classBand=label, region=roi, scale=10, geometries=True
)
# Add a random value field to the sample and use it to approximately split 80%
# of the features into a training set and 20% into a validation set.
sample = sample.randomColumn()
training_sample = sample.filter('random <= 0.8')
validation_sample = sample.filter('random > 0.8')
# Train a 10-tree random forest classifier from the training sample.
trained_classifier = ee.Classifier.smileRandomForest(10).train(
features=training_sample,
classProperty=label,
inputProperties=img.bandNames(),
)
# Get information about the trained classifier.
display('Results of trained classifier', trained_classifier.explain())
# Get a confusion matrix and overall accuracy for the training sample.
train_accuracy = trained_classifier.confusionMatrix()
display('Training error matrix', train_accuracy)
display('Training overall accuracy', train_accuracy.accuracy())
# Get a confusion matrix and overall accuracy for the validation sample.
validation_sample = validation_sample.classify(trained_classifier)
validation_accuracy = validation_sample.errorMatrix(label, 'classification')
display('Validation error matrix', validation_accuracy)
display('Validation accuracy', validation_accuracy.accuracy())
# Classify the reflectance image from the trained classifier.
img_classified = img.classify(trained_classifier)
# Add the layers to the map.
class_vis = {
'min': 0,
'max': 10,
'palette': [
'006400',
'ffbb22',
'ffff4c',
'f096ff',
'fa0000',
'b4b4b4',
'f0f0f0',
'0064c8',
'0096a0',
'00cf75',
'fae6a0',
],
}
m = geemap.Map()
m.set_center(-122.184, 37.796, 12)
m.add_layer(
img, {'bands': ['B11', 'B8', 'B3'], 'min': 100, 'max': 3500}, 'img'
)
m.add_layer(lc, class_vis, 'lc')
m.add_layer(img_classified, class_vis, 'Classified')
m.add_layer(roi, {'color': 'white'}, 'ROI', False, 0.5)
m.add_layer(training_sample, {'color': 'black'}, 'Training sample', False)
m.add_layer(
validation_sample, {'color': 'white'}, 'Validation sample', False
)
m
إنّ محتوى هذه الصفحة مرخّص بموجب ترخيص Creative Commons Attribution 4.0 ما لم يُنصّ على خلاف ذلك، ونماذج الرموز مرخّصة بموجب ترخيص Apache 2.0. للاطّلاع على التفاصيل، يُرجى مراجعة سياسات موقع Google Developers. إنّ Java هي علامة تجارية مسجَّلة لشركة Oracle و/أو شركائها التابعين.
تاريخ التعديل الأخير: 2025-07-26 (حسب التوقيت العالمي المتفَّق عليه)
[null,null,["تاريخ التعديل الأخير: 2025-07-26 (حسب التوقيت العالمي المتفَّق عليه)"],[[["\u003cp\u003eThe \u003ccode\u003eClassifier.explain()\u003c/code\u003e method provides descriptive information about a trained classifier in Earth Engine.\u003c/p\u003e\n"],["\u003cp\u003eThis information is returned as a dictionary and includes details such as the classifier type, number of trees (if applicable), and input properties used during training.\u003c/p\u003e\n"],["\u003cp\u003eThe example demonstrates how to train a random forest classifier using Sentinel-2 imagery and ESA WorldCover data.\u003c/p\u003e\n"],["\u003cp\u003eIt also shows how to assess classifier accuracy using confusion matrices and overall accuracy metrics on both training and validation datasets.\u003c/p\u003e\n"],["\u003cp\u003eFinally, it illustrates how to apply the trained classifier to an image for land cover classification.\u003c/p\u003e\n"]]],[],null,["# ee.Classifier.explain\n\nDescribe the results of a trained classifier.\n\n\u003cbr /\u003e\n\n| Usage | Returns |\n|------------------------|------------|\n| Classifier.explain`()` | Dictionary |\n\n| Argument | Type | Details |\n|--------------------|------------|-----------------------------|\n| this: `classifier` | Classifier | The classifier to describe. |\n\nExamples\n--------\n\n### Code Editor (JavaScript)\n\n```javascript\n// A Sentinel-2 surface reflectance image, reflectance bands selected,\n// serves as the source for training and prediction in this contrived example.\nvar img = ee.Image('COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG')\n .select('B.*');\n\n// ESA WorldCover land cover map, used as label source in classifier training.\nvar lc = ee.Image('ESA/WorldCover/v100/2020');\n\n// Remap the land cover class values to a 0-based sequential series.\nvar classValues = [10, 20, 30, 40, 50, 60, 70, 80, 90, 95, 100];\nvar remapValues = ee.List.sequence(0, 10);\nvar label = 'lc';\nlc = lc.remap(classValues, remapValues).rename(label).toByte();\n\n// Add land cover as a band of the reflectance image and sample 100 pixels at\n// 10 m scale from each land cover class within a region of interest.\nvar roi = ee.Geometry.Rectangle(-122.347, 37.743, -122.024, 37.838);\nvar sample = img.addBands(lc).stratifiedSample({\n numPoints: 100,\n classBand: label,\n region: roi,\n scale: 10,\n geometries: true\n});\n\n// Add a random value field to the sample and use it to approximately split 80%\n// of the features into a training set and 20% into a validation set.\nsample = sample.randomColumn();\nvar trainingSample = sample.filter('random \u003c= 0.8');\nvar validationSample = sample.filter('random \u003e 0.8');\n\n// Train a 10-tree random forest classifier from the training sample.\nvar trainedClassifier = ee.Classifier.smileRandomForest(10).train({\n features: trainingSample,\n classProperty: label,\n inputProperties: img.bandNames()\n});\n\n// Get information about the trained classifier.\nprint('Results of trained classifier', trainedClassifier.explain());\n\n// Get a confusion matrix and overall accuracy for the training sample.\nvar trainAccuracy = trainedClassifier.confusionMatrix();\nprint('Training error matrix', trainAccuracy);\nprint('Training overall accuracy', trainAccuracy.accuracy());\n\n// Get a confusion matrix and overall accuracy for the validation sample.\nvalidationSample = validationSample.classify(trainedClassifier);\nvar validationAccuracy = validationSample.errorMatrix(label, 'classification');\nprint('Validation error matrix', validationAccuracy);\nprint('Validation accuracy', validationAccuracy.accuracy());\n\n// Classify the reflectance image from the trained classifier.\nvar imgClassified = img.classify(trainedClassifier);\n\n// Add the layers to the map.\nvar classVis = {\n min: 0,\n max: 10,\n palette: ['006400' ,'ffbb22', 'ffff4c', 'f096ff', 'fa0000', 'b4b4b4',\n 'f0f0f0', '0064c8', '0096a0', '00cf75', 'fae6a0']\n};\nMap.setCenter(-122.184, 37.796, 12);\nMap.addLayer(img, {bands: ['B11', 'B8', 'B3'], min: 100, max: 3500}, 'img');\nMap.addLayer(lc, classVis, 'lc');\nMap.addLayer(imgClassified, classVis, 'Classified');\nMap.addLayer(roi, {color: 'white'}, 'ROI', false, 0.5);\nMap.addLayer(trainingSample, {color: 'black'}, 'Training sample', false);\nMap.addLayer(validationSample, {color: 'white'}, 'Validation sample', false);\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 Sentinel-2 surface reflectance image, reflectance bands selected,\n# serves as the source for training and prediction in this contrived example.\nimg = ee.Image(\n 'COPERNICUS/S2_SR/20210109T185751_20210109T185931_T10SEG'\n).select('B.*')\n\n# ESA WorldCover land cover map, used as label source in classifier training.\nlc = ee.Image('ESA/WorldCover/v100/2020')\n\n# Remap the land cover class values to a 0-based sequential series.\nclass_values = [10, 20, 30, 40, 50, 60, 70, 80, 90, 95, 100]\nremap_values = ee.List.sequence(0, 10)\nlabel = 'lc'\nlc = lc.remap(class_values, remap_values).rename(label).toByte()\n\n# Add land cover as a band of the reflectance image and sample 100 pixels at\n# 10 m scale from each land cover class within a region of interest.\nroi = ee.Geometry.Rectangle(-122.347, 37.743, -122.024, 37.838)\nsample = img.addBands(lc).stratifiedSample(\n numPoints=100, classBand=label, region=roi, scale=10, geometries=True\n)\n\n# Add a random value field to the sample and use it to approximately split 80%\n# of the features into a training set and 20% into a validation set.\nsample = sample.randomColumn()\ntraining_sample = sample.filter('random \u003c= 0.8')\nvalidation_sample = sample.filter('random \u003e 0.8')\n\n# Train a 10-tree random forest classifier from the training sample.\ntrained_classifier = ee.Classifier.smileRandomForest(10).train(\n features=training_sample,\n classProperty=label,\n inputProperties=img.bandNames(),\n)\n\n# Get information about the trained classifier.\ndisplay('Results of trained classifier', trained_classifier.explain())\n\n# Get a confusion matrix and overall accuracy for the training sample.\ntrain_accuracy = trained_classifier.confusionMatrix()\ndisplay('Training error matrix', train_accuracy)\ndisplay('Training overall accuracy', train_accuracy.accuracy())\n\n# Get a confusion matrix and overall accuracy for the validation sample.\nvalidation_sample = validation_sample.classify(trained_classifier)\nvalidation_accuracy = validation_sample.errorMatrix(label, 'classification')\ndisplay('Validation error matrix', validation_accuracy)\ndisplay('Validation accuracy', validation_accuracy.accuracy())\n\n# Classify the reflectance image from the trained classifier.\nimg_classified = img.classify(trained_classifier)\n\n# Add the layers to the map.\nclass_vis = {\n 'min': 0,\n 'max': 10,\n 'palette': [\n '006400',\n 'ffbb22',\n 'ffff4c',\n 'f096ff',\n 'fa0000',\n 'b4b4b4',\n 'f0f0f0',\n '0064c8',\n '0096a0',\n '00cf75',\n 'fae6a0',\n ],\n}\nm = geemap.Map()\nm.set_center(-122.184, 37.796, 12)\nm.add_layer(\n img, {'bands': ['B11', 'B8', 'B3'], 'min': 100, 'max': 3500}, 'img'\n)\nm.add_layer(lc, class_vis, 'lc')\nm.add_layer(img_classified, class_vis, 'Classified')\nm.add_layer(roi, {'color': 'white'}, 'ROI', False, 0.5)\nm.add_layer(training_sample, {'color': 'black'}, 'Training sample', False)\nm.add_layer(\n validation_sample, {'color': 'white'}, 'Validation sample', False\n)\nm\n```"]]