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ItemCf:UsersPerItem推荐 (ItemCfUsersPerItemRecommBatchOp)

Java 类名:com.alibaba.alink.operator.batch.recommendation.ItemCfUsersPerItemRecommBatchOp

Python 类名:ItemCfUsersPerItemRecommBatchOp

功能介绍

用ItemCF模型 为item推荐user list。

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
itemCol Item列列名 Item列列名 String ✓
recommCol 推荐结果列名 推荐结果列名 String ✓
excludeKnown 排除已知的关联 推荐结果中是否排除训练数据中已知的关联 Boolean false
initRecommCol 初始推荐列列名 初始推荐列列名 String 所选列类型为 [M_TABLE, STRING] null
k 推荐TOP数量 推荐TOP数量 Integer 10
reservedCols 算法保留列名 算法保留列 String[] null
numThreads 组件多线程线程个数 组件多线程线程个数 Integer 1

代码示例

Python 代码

from pyalink.alink import *

import pandas as pd

useLocalEnv(1)

df_data = pd.DataFrame([
    [1, 1, 0.6],
    [2, 2, 0.8],
    [2, 3, 0.6],
    [4, 1, 0.6],
    [4, 2, 0.3],
    [4, 3, 0.4],
])

data = BatchOperator.fromDataframe(df_data, schemaStr='user bigint, item bigint, rating double')

model = ItemCfTrainBatchOp()\
    .setUserCol("user")\
    .setItemCol("item")\
    .setRateCol("rating").linkFrom(data);

predictor = ItemCfUsersPerItemRecommBatchOp()\
    .setItemCol("item")\
    .setReservedCols(["item"])\
    .setK(1)\
    .setRecommCol("prediction_result");

predictor.linkFrom(model, data).print()

Java 代码

import org.apache.flink.types.Row;

import com.alibaba.alink.operator.batch.BatchOperator;
import com.alibaba.alink.operator.batch.recommendation.ItemCfTrainBatchOp;
import com.alibaba.alink.operator.batch.recommendation.ItemCfUsersPerItemRecommBatchOp;
import com.alibaba.alink.operator.batch.source.MemSourceBatchOp;
import org.junit.Test;

import java.util.Arrays;
import java.util.List;

public class ItemCfUsersPerItemRecommBatchOpTest {
	@Test
	public void testItemCfUsersPerItemRecommBatchOp() throws Exception {
		List <Row> df_data = Arrays.asList(
			Row.of(1, 1, 0.6),
			Row.of(2, 2, 0.8),
			Row.of(2, 3, 0.6),
			Row.of(4, 1, 0.6),
			Row.of(4, 2, 0.3),
			Row.of(4, 3, 0.4)
		);
		BatchOperator <?> data = new MemSourceBatchOp(df_data, "user int, item int, rating double");
		BatchOperator <?> model = new ItemCfTrainBatchOp()
			.setUserCol("user")
			.setItemCol("item")
			.setRateCol("rating").linkFrom(data);
		BatchOperator <?> predictor = new ItemCfUsersPerItemRecommBatchOp()
			.setItemCol("item")
			.setReservedCols("item")
			.setK(1)
			.setRecommCol("prediction_result");
		predictor.linkFrom(model, data).print();
	}
}

运行结果

item prediction_result
1 {“user”:“[2]”,“score”:“[0.21698238771519462]”}
2 {“user”:“[2]”,“score”:“[0.29215236292253793]”}
3 {“user”:“[2]”,“score”:“[0.38953648389671724]”}
1 {“user”:“[2]”,“score”:“[0.21698238771519462]”}
2 {“user”:“[2]”,“score”:“[0.29215236292253793]”}
3 {“user”:“[2]”,“score”:“[0.38953648389671724]”}