To to extract and display the partitioning/distribution map for a partition group you have to use the command below:

db2gpmap
<-d [DatabaseName]>
<-g [PartitionGroup]>
<-m [MapFileName]>
<-t [TableName]>
<-h>

Example:

To generate a partitioning (distribution) map for a partition group named PG_123 in a database named TEST and write it to a file named PG_123map.txt, you would execute a db2gpmap command that looks something like this:

db2gpmap -d TEST -g PG_123 -m PG_123map.txt

And, assuming the partition group named PG_123 spans three database partitions, the first eight lines of the output file produced (PG123map.txt) would look like this:

1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3
1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3 1 2 3

(The upper-left corner corresponds to the partition ID at element 0 of the partitioning map. The map is read by moving from left to right and down, line-by-line.)