Java 类名:com.alibaba.alink.operator.batch.feature.VectorChiSqSelectorBatchOp
Python 类名:VectorChiSqSelectorBatchOp
功能介绍
针对vector数据,进行特征筛选
参数说明
名称 | 中文名称 | 描述 | 类型 | 是否必须? | 取值范围 | 默认值 |
---|---|---|---|---|---|---|
labelCol | 标签列名 | 输入表中的标签列名 | String | ✓ | ||
selectedCol | 选中的列名 | 计算列对应的列名 | String | ✓ | 所选列类型为 [DENSE_VECTOR, SPARSE_VECTOR, STRING, VECTOR] | |
fdr | 发现阈值 | 发现阈值, 默认值0.05 | Double | 0.05 | ||
fpr | p value的阈值 | p value的阈值,默认值0.05 | Double | 0.05 | ||
fwe | 错误率阈值 | 错误率阈值, 默认值0.05 | Double | 0.05 | ||
numTopFeatures | 最大的p-value列个数 | 最大的p-value列个数, 默认值50 | Integer | 50 | ||
percentile | 筛选的百分比 | 筛选的百分比,默认值0.1 | Double | 0.1 | ||
selectorType | 筛选类型 | 筛选类型,包含”NumTopFeatures”,”percentile”, “fpr”, “fdr”, “fwe”五种。 | String | “NumTopFeatures”, “PERCENTILE”, “FPR”, “FDR”, “FWE” | “NumTopFeatures” |
代码示例
以下代码仅用于示意,可能需要修改部分代码或者配置环境后才能正常运行!
Python 代码
无python接口
Java 代码
package javatest.com.alibaba.alink.batch.feature;
import org.apache.flink.types.Row;
import com.alibaba.alink.operator.batch.BatchOperator;
import com.alibaba.alink.operator.batch.feature.VectorChiSqSelectorBatchOp;
import com.alibaba.alink.operator.batch.source.MemSourceBatchOp;
import org.junit.Test;
import java.util.Arrays;
public class VectorChiSqSelectorBatchOpTest {
@Test
public void testVectorChiSqSelectorBatchOp() throws Exception {
Row[] testArray = new Row[] {
Row.of(7, "0.0 0.0 18.0 1.0", 1.0),
Row.of(8, "0.0 1.0 12.0 0.0", 0.0),
Row.of(9, "1.0 0.0 15.0 0.1", 0.0),
};
String[] colNames = new String[] {"id", "features", "clicked"};
MemSourceBatchOp source = new MemSourceBatchOp(Arrays.asList(testArray), colNames);
VectorChiSqSelectorBatchOp test = new VectorChiSqSelectorBatchOp()
.setSelectedCol("features")
.setLabelCol("clicked");
test.linkFrom(source);
test.lazyPrintModelInfo();
BatchOperator.execute();
}
}
运行结果
------------------------- ChisqSelectorModelInfo -------------------------
Number of Selector Features: 4
Number of Features: 4
Type of Selector: NumTopFeatures
Number of Top Features: 50
Selector Indices:
|VectorIndex|ChiSquare|PValue| DF|Selected|
|-----------|---------|------|---|--------|
| 3| 3|0.2231| 2| true|
| 2| 3|0.2231| 2| true|
| 0| 0.75|0.3865| 1| true|
| 1| 0.75|0.3865| 1| true|