Talk:Signed overpunch
Add topic | This article has not yet been rated on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
| |||||||||||
Right or left?
[edit]Is signed overpunch always on the rightmost column? I know it works that way with S/360 PACK and UNPACK, but it actually comes from the days of unit record machines. You can do the sign pass with any column as a pass through a card sorter. Gah4 (talk) 04:56, 23 March 2017 (UTC)
- Not punch cards, but I had to work with a financial software lately that would use this system of writing negative numbers. By peeking at the serial link I found that it would write it in the way described in this article, always using the least significant decimal digit. AyrA (talk) 20:56, 4 October 2017 (UTC)
ASCII
[edit]I believe that the DEC COBOL compilers supported this, especially if it is part of the COBOL standard. That might be a good reference for ASCII signed overpunch. Gah4 (talk) 01:48, 30 November 2018 (UTC)
- yes, thanks. I was just checking the IBM reference as well. DEC, IBM, and Iron Spring PL/I support signed overpunches using the same characters in ASCII and EBCDIC. I'm going to add some text to that effect. Peter Flass (talk) 02:04, 30 November 2018 (UTC)
card sorter
[edit]As well as I know, signed overpunch goes back earlier than computers. The IBM type 83 sorter, for example, could sort a deck of card using radix sort, column by column, either digits or zones. So, could sort a field using signed overpunch. Gah4 (talk) 21:52, 15 March 2026 (UTC)