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FeatureExtractorFunction[…]

表示由 FeatureExtraction 生成的特征提取程序函数.

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范例  
基本范例  
范围  
可能存在的问题  
参见
相关指南
历史
按以下格式引用：

FeatureExtractorFunction

FeatureExtractorFunction[…]

表示由 FeatureExtraction 生成的特征提取程序函数.

更多信息和选项

范例

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基本范例  (1)

在简单数据集上训练 FeatureExtractorFunction：

Wolfram Language code: fe = FeatureExtraction[{{1.4, "A"}, {1.5, "A"}, {2.3, "B"}, {5.4, "B"}}]

从新的范例提取特征：

Wolfram Language code: fe[{2.4, "A"}]

从一个范例列表提取特征：

Wolfram Language code: fe[{{2.4, "A"}, {3.7, "B"}}]

范围  (5)

有些特征提取程序仅能进行逆向提取的近似：

Wolfram Language code: fe = FeatureExtraction[{{1.4, 1.4, 5.4, 5.2}, {1.5, 1.5, 6.4, 5.2}, {1.2, 1.2, 6.2, 5.2}, {1.6, 1.6, 4.3, 5.2}}, "DimensionReducedVector"]
Wolfram Language code: features = fe[{1.1, 1.2, 5.1, 5.7}]
Wolfram Language code: fe[features, "OriginalData"]

FeatureExtraction 的属性 "ReconstructedData" 可用于获得提取和重构后的数据：

Wolfram Language code: FeatureExtraction[{{1.4, 1.4, 5.4, 5.2}, {1.5, 1.5, 6.4, 5.2}, {1.2, 1.2, 6.2, 5.2}, {1.6, 1.6, 4.3, 5.2}}, "DimensionReducedVector", "ReconstructedData"]

有些特征提取程序不能逆向：

Wolfram Language code: FeatureExtraction[{[image], [image] , [image], [image]}, "ImageFeatures", "ReconstructedData"]

从包含缺失值的数据集训练特征抽取程序：

Wolfram Language code: fe = FeatureExtraction[{{1.4, Missing[], "A"}, {1.5, 50.2, "A"}, {Missing[], 42.3, "B"}, {5.4, 61.7, "B"}}]

特征提取器现在表明缺失值被估算. 即使值缺失，特征提取器也可以提取特征：

Wolfram Language code: fe[{3.4, Missing[], "B"}]

从经过训练的 FeatureExtractorFunction 获取 Information：

Wolfram Language code: Information[FeatureExtractorFunction[Association["ExampleNumber" -> 4, "Preprocessor" -> MachineLearning`MLProcessor["ToMLDataset", Association["Input" -> Association["age" -> Association["Type" -> "Numerical"], "gender" -> Association["Type" - ... ate" -> DateObject[{2025, 5, 2, 13, 0, 39.042795`8.344115878952366}, "Instant", "Gregorian", 2.], "ProcessorCount" -> 10, "ProcessorType" -> "ARM64", "OperatingSystem" -> "MacOSX", "SystemWordLength" -> 64, "Evaluations" -> {}]]]]

查找可用属性：

Wolfram Language code: Information[FeatureExtractorFunction[Association["ExampleNumber" -> 4, "Preprocessor" -> MachineLearning`MLProcessor["ToMLDataset", Association["Input" -> Association["age" -> Association["Type" -> "Numerical"], "gender" -> Association["Type" - ... ate" -> DateObject[{2025, 5, 2, 13, 0, 39.042795`8.344115878952366}, "Instant", "Gregorian", 2.], "ProcessorCount" -> 10, "ProcessorType" -> "ARM64", "OperatingSystem" -> "MacOSX", "SystemWordLength" -> 64, "Evaluations" -> {}]]], "Properties"]

获取特征名称和训练样例的信息：

Wolfram Language code: Information[FeatureExtractorFunction[Association["ExampleNumber" -> 4, "Preprocessor" -> MachineLearning`MLProcessor["ToMLDataset", Association["Input" -> Association["age" -> Association["Type" -> "Numerical"], "gender" -> Association["Type" - ... ate" -> DateObject[{2025, 5, 2, 13, 0, 39.042795`8.344115878952366}, "Instant", "Gregorian", 2.], "ProcessorCount" -> 10, "ProcessorType" -> "ARM64", "OperatingSystem" -> "MacOSX", "SystemWordLength" -> 64, "Evaluations" -> {}]]], {"FeatureNames", "ExampleNumber"}]

可能存在的问题  (1)

通过键提取旧的 FeatureExtractorFunction ：

Wolfram Language code: fe = FeatureExtractorFunction[Association["ExampleNumber" -> 0, "Preprocessor" -> MachineLearning`MLProcessor["ToMLDataset", Association["Input" -> Association["input" -> Association["Type" -> "Text"]], "Output" -> Association["f1" -> Asso ... "Date" -> DateObject[{2026, 1, 28, 15, 36, 22.701151`8.10862286062899}, "Instant", "Gregorian", 0.], "ProcessorCount" -> 10, "ProcessorType" -> "ARM64", "OperatingSystem" -> "MacOSX", "SystemWordLength" -> 64, "Evaluations" -> {}]]];

使用缺失或不正确的特征名称将导致错误或内容缺失：

Wolfram Language code: fe["Hello"]
Wolfram Language code: fe[<|"Input" -> "Hello"|>]

用 Information 获取特征的名称：

Wolfram Language code: Information[fe, "FeatureNames"]

纠正特征的名称：

Wolfram Language code: fe[<|"input" -> "Hello"|>]
Wolfram Research (2016)，FeatureExtractorFunction，Wolfram 语言函数，https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html （更新于 2017 年）.

文本

Wolfram Research (2016)，FeatureExtractorFunction，Wolfram 语言函数，https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html （更新于 2017 年）.

CMS

Wolfram 语言. 2016. "FeatureExtractorFunction." Wolfram 语言与系统参考资料中心. Wolfram Research. 最新版本 2017. https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html.

APA

Wolfram 语言. (2016). FeatureExtractorFunction. Wolfram 语言与系统参考资料中心. 追溯自 https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html 年

BibTeX

@misc{reference.wolfram_2026_featureextractorfunction, author="Wolfram Research", title="{FeatureExtractorFunction}", year="2017", howpublished="\url{https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html}", note=[Accessed: 10-September-2026]}

BibLaTeX

@online{reference.wolfram_2026_featureextractorfunction, organization={Wolfram Research}, title={FeatureExtractorFunction}, year={2017}, url={https://reference.wolfram.com/language/ref/FeatureExtractorFunction.html}, note=[Accessed: 10-September-2026]}