Question

我仅尝试打印此COBOL表的元素之一，但是似乎在理解COBOL中的数组（表）如何工作时遇到了麻烦！

data division.
       working-storage section.
       01 m-airlines.
         05 m-united occurs 3 times.
           10 m-u-a330 pic 9(1) value 3.
           10 m-u-a321 pic 9(1) value 1.
           10 m-u-a300 pic 9(1) value 5.
         05 m-delta occurs 3 times.
           10 m-dl-a330 pic 9(2) value 35.
           10 m-dl-a321 pic 9(2) value 27.
           10 m-dl-b777 pic 9(2) value 20.

       procedure division.
           display "number of Delta's Airbus a330: " m-delta(1,1).

我收到此错误：

下标过多。

Answer 1

根据代码，您有两个表元素（或）2个一维表m-united和m-delta。要引用表中的项目，应使用表元素的数据名称，并在括号中使用它的出现编号（下标）。这称为下标。正如@Bruce Martin在评论中提到的那样，您应该尝试m-delta(1)引用表中的第一个元素。

您引用表格元素m-delta(1,1)的方式适用于二维表格。这种引用方式是错误的，因为您尚未定义2D表。而是定义了2个一维表。有关创建2D / 3D表的更多信息，请参见Nesting tables。

Answer 2

这些是您的代码生成的表。这不是您的意图。

             +-------------+-------------+-------------+
m-united(1): | m-u-a330(1) | m-u-a321(1) | m-u-a300(1) |
             +-------------+-------------+-------------+
m-united(2): | m-u-a330(2) | m-u-a321(2) | m-u-a300(2) |
             +-------------+-------------+-------------+
m-united(3): | m-u-a330(3) | m-u-a321(3) | m-u-a300(3) |
             +-------------+-------------+-------------+

            +--------------+--------------+--------------+
m-delta(1): | m-dl-a330(1) | m-dl-a321(1) | m-dl-b777(1) |
            +--------------+--------------+--------------+
m-delta(2): | m-dl-a330(2) | m-dl-a321(2) | m-dl-b777(2) |
            +--------------+--------------+--------------+
m-delta(3): | m-dl-a330(3) | m-dl-a321(3) | m-dl-b777(3) |
            +--------------+--------------+--------------+

也许这就是您想要的：

01 AIRLINE-TABLE.
   05 M-U-A330     PIC 99 VALUE 3.
   05 M-U-A321     PIC 99 VALUE 1.
   05 M-U-A300     PIC 99 VALUE 5.
   05 M-U-B777     PIC 99 VALUE 0.
   05 M-D-A330     PIC 99 VALUE 35.
   05 M-D-A321     PIC 99 VALUE 27
   05 M-D-A300     PIC 99 VALUE 0.
   05 M-D-B777     PIC 99 VALUE 20.
01 FILLER REDEFINES AIRLINE-TABLE.
   05 AIRLINE OCCURS 2 TIMES.
      10 NUM-A330  PIC 99.
      10 NUM-A321  PIC 99.
      10 NUM-A300  PIC 99.
      10 NUM-B777  PIC 99.

它将生成：

            +-------------+-------------+-------------+-------------+
airline(1): | num-a330(1) | num-a321(1) | num-a300(1) | num-b777(1) |
            +-------------+-------------+-------------+-------------+
airline(2): | num-a330(2) | num-a321(2) | num-a300(2) | num-b777(2) |
            +-------------+-------------+-------------+-------------+

... DISPLAY "Number of Delta's Airbus a330 : " num-a330(2)

或者这个：

01 AIRLINE-TABLE.
   05 M-U-A330     PIC 99 VALUE 3.
   05 M-U-A321     PIC 99 VALUE 1.
   05 M-U-A300     PIC 99 VALUE 5.
   05 M-U-B777     PIC 99 VALUE 0.
   05 M-D-A330     PIC 99 VALUE 35.
   05 M-D-A321     PIC 99 VALUE 27
   05 M-D-A300     PIC 99 VALUE 0.
   05 M-D-B777     PIC 99 VALUE 20.
01 FILLER REDEFINES AIRLINE-TABLE.
   05 AIRLINE OCCURS 2 TIMES.
      10 AIRPLANE OCCURS 4 TIMES.
         15 NUM-PLANES PIC 99.

给出

            +------------------+------------------+------------------+------------------+
airline(1): | num-planes(1, 1) | num-planes(1, 2) | num-planes(1, 3) | num-planes(1, 4) |
            +------------------+------------------+------------------+------------------+
airline(2): | num-planes(2, 1) | num-planes(2, 2) | num-planes(2, 3) | num-planes(2, 4) |
            +------------------+------------------+------------------+------------------+

... DISPLAY "Number of Delta's Airbus a330 : " num-planes(2, 1)

如何在COBOL中的数组（表）中打印迭代？

2 个答案: