下面的方法将适用于您的情况。
输入：

1,0.0,0.0
2,-0.1,-0.1
3,1.0,-2.2

Pig手稿：

A = LOAD 'input' USING PigStorage(',') AS(index:int,x:double,y:double);
B = FILTER A BY index>=1;
C = FILTER A BY index>1;
D = FOREACH C GENERATE ($0-1) AS dindex,index,x,y;
E = JOIN B BY index, D BY dindex;
F = FOREACH E GENERATE TOBAG(TOTUPLE(B::index,B::x,B::y),TOTUPLE(D::index,D::x,D::y));
DUMP F;

输出：

({(1,0.0,0.0),(2,-0.1,-0.1)})
({(2,-0.1,-0.1),(3,1.0,-2.2)})

您可以使用以下查询（注解中的解释）。

-- load relation
R = LOAD 'data.txt' USING PigStorage(',') AS (index,x,y);

-- project each tuple to 2 different keys
-- one with index and one with index+1
R1 = FOREACH R GENERATE index+0, index, x, y;
R2 = FOREACH R GENERATE index+1, index, x, y;

-- group
result = COGROUP R1 by $0, R2 by $0;

-- clean out wrong combinations
result2 = filter result by NOT(IsEmpty(R1)) and NOT(IsEmpty(R2));

-- flatten the results
result3 = FOREACH result2 GENERATE FLATTEN(R1), FLATTEN(R2);
result4 = FOREACH result3 GENERATE (R1::index,R1::x,R1::y), (R2::index,R2::x,R2::y);

我用来测试的文件包含以下内容：

1,0.0,0.0
2,-0.1,-0.1
3,1.0,-2.2

请注意，括号不存在，但可以使用简单的预处理脚本将其过滤掉。
中间结果的转储为： DUMP R;(1,0.0,0.0) (2,-0.1,-0.1) (3,1.0,-2.2)DUMP R1;((1,1,0.0,0.0)) ((2,2,-0.1,-0.1)) ((3,3,1.0,-2.2))DUMP R2;((1,1,0.0,0.0)) ((2,2,-0.1,-0.1)) ((3,3,1.0,-2.2))DUMP result;(1,{(1,1,0.0,0.0)},{}) (2,{(2,2,-0.1,-0.1)},{(2,1,0.0,0.0)}) (3,{(3,3,1.0,-2.2)},{(3,2,-0.1,-0.1)}) (4,{},{(4,3,1.0,-2.2)})DUMP result2;(2,{(2,2,-0.1,-0.1)},{(2,1,0.0,0.0)}) (3,{(3,3,1.0,-2.2)},{(3,2,-0.1,-0.1)})DUMP result3;(2,2,-0.1,-0.1,2,1,0.0,0.0) (3,3,1.0,-2.2,3,2,-0.1,-0.1)DUMP result4; ```
((2,-0.1,-0.1),(1,0.0,0.0))
((3,1.0,-2.2),(2,-0.1,-0.1))