Java 类名:com.alibaba.alink.operator.batch.dataproc.ImputerTrainBatchOp
Python 类名:ImputerTrainBatchOp
功能介绍
数据缺失值模型训练
缺失值填充支持4种策略,最大值、最小值、均值、指定数值。当策略为指定数值时,需要设置参数fillValue。
模型生成后处理其他数据参考ImputerPredictBatchOp
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 |
---|---|---|---|---|---|---|
selectedCols | 选择的列名 | 计算列对应的列名列表 | String[] | ✓ | 所选列类型为 [BIGDECIMAL, BIGINTEGER, BYTE, DOUBLE, FLOAT, INTEGER, LONG, SHORT] | |
fillValue | 填充缺失值 | 自定义的填充值。当strategy为value时,读取fillValue的值 | String | null | ||
strategy | 缺失值填充规则 | 缺失值填充的规则,支持mean,max,min或者value。选择value时,需要读取fillValue的值 | String | “MEAN”, “MIN”, “MAX”, “VALUE” | “MEAN” |
代码示例
Python 代码
from pyalink.alink import *
import pandas as pd
useLocalEnv(1)
df_data = pd.DataFrame([
["a", 10.0, 100],
["b", -2.5, 9],
["c", 100.2, 1],
["d", -99.9, 100],
["a", 1.4, 1],
["b", -2.2, 9],
["c", 100.9, 1],
[None, None, None]
])
colnames = ["col1", "col2", "col3"]
selectedColNames = ["col2", "col3"]
inOp = BatchOperator.fromDataframe(df_data, schemaStr='col1 string, col2 double, col3 double')
# train
trainOp = ImputerTrainBatchOp()\
.setSelectedCols(selectedColNames)
model = trainOp.linkFrom(inOp)
# batch predict
predictOp = ImputerPredictBatchOp()
predictOp.linkFrom(model, inOp).print()
# stream predict
sinOp = StreamOperator.fromDataframe(df_data, schemaStr='col1 string, col2 double, col3 double')
predictStreamOp = ImputerPredictStreamOp(model)
predictStreamOp.linkFrom(sinOp).print()
StreamOperator.execute()
Java 代码
import org.apache.flink.types.Row;
import com.alibaba.alink.operator.batch.BatchOperator;
import com.alibaba.alink.operator.batch.dataproc.ImputerPredictBatchOp;
import com.alibaba.alink.operator.batch.dataproc.ImputerTrainBatchOp;
import com.alibaba.alink.operator.batch.source.MemSourceBatchOp;
import com.alibaba.alink.operator.stream.StreamOperator;
import com.alibaba.alink.operator.stream.dataproc.ImputerPredictStreamOp;
import com.alibaba.alink.operator.stream.source.MemSourceStreamOp;
import org.junit.Test;
import java.util.Arrays;
import java.util.List;
public class ImputerTrainBatchOpTest {
@Test
public void testImputerTrainBatchOp() throws Exception {
List <Row> df_data = Arrays.asList(
Row.of("a", 10.0, 100),
Row.of("b", -2.5, 9),
Row.of("c", 100.2, 1),
Row.of("d", -99.9, 100),
Row.of("a", 1.4, 1),
Row.of("b", -2.2, 9),
Row.of("c", 100.9, 1),
Row.of(null, null, null)
);
String[] selectedColNames = new String[] {"col2", "col3"};
BatchOperator <?> inOp = new MemSourceBatchOp(df_data, "col1 string, col2 double, col3 int");
BatchOperator <?> trainOp = new ImputerTrainBatchOp()
.setSelectedCols(selectedColNames);
BatchOperator model = trainOp.linkFrom(inOp);
BatchOperator <?> predictOp = new ImputerPredictBatchOp();
predictOp.linkFrom(model, inOp).print();
StreamOperator <?> sinOp = new MemSourceStreamOp(df_data, "col1 string, col2 double, col3 int");
StreamOperator <?> predictStreamOp = new ImputerPredictStreamOp(model);
predictStreamOp.linkFrom(sinOp).print();
StreamOperator.execute();
}
}
运行结果
| col1 | col2 | col3 | | —- | —- | —- |
| a | 10.000000 | 100 |
| b | -2.500000 | 9 |
| c | 100.200000 | 1 |
| d | -99.900000 | 100 |
| a | 1.400000 | 1 |
| b | -2.200000 | 9 |
| c | 100.900000 | 1 |
| null | 15.414286 | 31 |