場景: 我有記錄的事件一樣在這個CSV如服務: #TimeStamp, Name, ColorOfPullover
TimeStamp01, Peter, Green
TimeStamp02, Bob, Blue
TimeStamp03, Peter, Green
TimeStamp04, Peter, Red
TimeStamp05, Peter, Green
事件例如彼得穿着綠色
計算平均我有兩個dataframes: 第一數據幀classRecord有10個不同的條目像以下: Class, Calculation
first, Average
Second, Sum
Third, Average
第二數據幀studentRecord具有圍繞50K條目像以下: Name, height, Camp, Class
Shae, 152, yellow, first
我試圖通過製作電影推薦系統來練習Big Data Mapreduce。我的代碼: *imports
public class MRS {
public static class Map extends Mapper<LongWritable, Text, Text, Text> {
public void map(LongWritable key, Text valu