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From: LR on 9 Aug 2010 00:25 Dr Ivan D. Reid wrote: > On Sun, 8 Aug 2010 21:47:15 +1000, robin <robin51(a)dodo.com.au> > wrote in <4c5e9948$0$34572$c30e37c6(a)exi-reader.telstra.net>: > "Dr Ivan > D. Reid" <Ivan.Reid(a)ivan.fsnet.co.uk> wrote in message > news:slrni5nem7.1uk.Ivan.Reid(a)smtp.orangehome.co.uk... > >> | My experience with a Cyber in 1978 was that it had a 60-bit word >> | but integer multiply/divide only worked up to 48 bits. To shift a 48-bit >> | integer to 60 bits to add a 5th 12-bit byte I had to use successive adds >> | (i=i+i). > >> There was a shift instruction that would have done the job in one step. > > In FORTRAN? > An intrinsic function. You can find it here http://www.bitsavers.org/pdf/cdc/cyber/lang/fortran/60305600A_FTN_Extd_V4_Oct71.pdf on page 1-8-4. LR
From: Nick Maclaren on 9 Aug 2010 03:39 In article <i3n9vq$6e0$1(a)speranza.aioe.org>, glen herrmannsfeldt <gah(a)ugcs.caltech.edu> wrote: > >I don't have a VS Fortran manual, so it might have changed, but >likely not, other than removing the feature. For S/360 (and >successors) it takes one instruction to reference a local variable, >but two to reference a variable by reference. Call by value >result is, in most cases, more efficient. It is often more more efficient, because it is more cache-friendly. The reason that it isn't much used is fashion, not engineering. Regards, Nick Maclaren.
From: Nick Maclaren on 9 Aug 2010 07:32 In article <4c5f685c$0$56742$c30e37c6(a)exi-reader.telstra.net>, robin <robin51(a)dodo.com.au> wrote: > >Instead of making insulting and derogatory remarks about someone else >when you are shown up to be incorrect, why don't you take a good look >at yourself !! I recommend that you read the gospel of Matthew, specifically 7:1-5. Regards, Nick Maclaren.
From: feenberg on 9 Aug 2010 09:07 On Aug 9, 12:09 am, LR <lr...(a)superlink.net> wrote: > mecej4 wrote: > > It seems to me that the last few posts in this thread (about 64 or 65 > > characters on the CDC) indicate that the colon may have been used as an > > escape character, somewhat like the backslash, \ , in C, with a pair of > > backslashes being then needed to signify the literal character. > > > This is speculation on my part, but this may throw some light on why two > > colons had quite a different effect than the once-repeated effect of a > > single colon. > > Not quite. For one thing, it's not really colons, just two octal zero > six bit characters in the last position of a 60 bit word. But you could > have the line or record or whatever we might call it end before those > last two characters, for example, for a seven or 17 or 27 etc character > line, then you'd have three octal zero characters terminate the line. > For a six or 16 or 26 etc character line, four octal zero characters > terminate the line and so on. A nine or 19 or 29 etc, character line > would have had 11 zero octal characters terminate the line. And finally > a ten or 20 or 30 etc character line would have ten octal zero > characters terminate the line. > > This implies that if we're to follow Robin's convention, it would really > be more accurate to say that there were 64 display characters + 11 > termination characters for zero terminated records = 75 characters. But > of course, CDC referred to them as the 63 and 64 Display character sets. > > As has been pointed out this leads to two problems. 1) You might > possibly end up with two colons on in the last two positions of a word, > resulting in a problem. 2) Ending a line with any number of colons using > Display 64 wasn't possible. > > Appendix A in the PLI reference has some nice tables. The footnotes tell > more of the story.http://www.bitsavers.org/pdf/cdc/cyber/lang/pl1/60388100B_PL_I_Versio... > > LR Anyone interested in the history of character set coding is referred to http://www.amazon.com/dp/0201144603 which is a history of Coded Character Sets from pre-history through EBCDIC and ASCII, with lots of information about how they came about. I read it 30 years ago. Daniel Feenberg
From: Harold Stevens on 9 Aug 2010 09:39
In <i3op00$57s$1(a)gosset.csi.cam.ac.uk> Nick Maclaren: [Snip...] > Matthew, specifically 7:1-5 Leave it to "robin" to quibble now about particular translation minutiae. -- Regards, Weird (Harold Stevens) * IMPORTANT EMAIL INFO FOLLOWS * Pardon any bogus email addresses (wookie) in place for spambots. Really, it's (wyrd) at airmail, dotted with net. DO NOT SPAM IT. I toss GoogleGroup (http://twovoyagers.com/improve-usenet.org/). |