Help me with HP50g -DOSUBS !

[carlovan]

I started programming in RPN with the HP33E (1974) and continued up to the HP41C.
When I bought the new HP50G I encountered a lot of problems to understand the UserRPN: manuals are not exhaustive !
But the worst came with the command DOSUBS: I really cannot understand how it works: Is there any gentle soul who can write a @comment after every line of the “explanatory example” programs of the RPN Programming manual (!) ?


Example 1:
{ A B C D E }
« - »
DOSUBS
returns { 'A-B' 'B-C' 'C-D' 'D-E' }.

Example 2:
{ A B C }
2
« DUP * * »
DOSUBS
returns { 'A*(B*B)' 'B*(C*C)' }.

Example 3: Entering:
{ 1 2 3 4 5 }
« → a b
« CASE 'NSUB==1' THEN a END
'NSUB==ENDSUB' THEN b END
'a+b' EVAL END » »
DOSUBS
returns { 1 5 7 5 }