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Leo B.

 Discussion on question by Leo B.: Whi…

Imported from a comment discussion on retrocomputing.stackexch...
Leo B.
Aug 29, 2024 21:26
@davolfman If there is a multi-dimensional array stored in memory, and if for such array elements that are adjacent in memory and have all indices but one the same, and the remaining index differing by one, the differing index is the leftmost one, then the array storage policy is said to be column-major; if it is the rightmost one, it is said to be row-major.
Leo B.
Aug 29, 2024 21:26
@JeremyP Precisely. That's why the sentence in bold in the question uses "multi-dimensional array types" rather than "multi-dimensional arrays".
Leo B.
Aug 29, 2024 21:26
@thebusybee this is the nature of multidimensional arrays Of course it isn't. A multidimensional array can be represented as a tree-based map or a hash map from index tuples to values, FWIW.
Leo B.
Aug 29, 2024 21:26
@thebusybee Because the C language syntax doesn't allow defining multi-dimensional arrays, and they have to be simulated using arrays of arrays.
Leo B.
Aug 29, 2024 21:26
@dave A legal PL/I program is not able to recognize that, contrary to your criterion.
Leo B.
Aug 29, 2024 21:26
@dave For that reason there is "/environment" In the question title. Also, what language features justify inclusion of PL/I and Pascal in the "row-major" list?
Leo B.
Aug 29, 2024 21:26
@dave True, and how does that observation affect the question? Or am I missing the point?
Leo B.
Aug 29, 2024 21:26
@dave Why the restriction "for a legal program"? It is my understanding that it was possible to perceive the ordering by a difference in performance of native vs transposed matrix traversal by nested loops as soon as mid-1960s.
 

 Discussion on question by qwr: Which …

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Leo B.
Aug 3, 2024 11:10
Neither ABC nor SETL, precursors to Python, have the feature.
 

 Discussion on answer by Raffzahn: Whi…

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Leo B.
Feb 20, 2024 14:54
@Raffzahn Are you saying that stopping the machine, then powering it down for the holidays, then powering it back on and pressing the "go" button, or its equivalent, would just work, as if nothing has happened? If so, then good; /360 did not need OS support for hibernation, and therefore is out of scope of the question. Which was the first OS supporting running on a platform which needed OS support?
Leo B.
Feb 20, 2024 14:54
@trickly Even without that requirement, and with core memory, the OS must have had a special provision to save volatile registers somewhere upon a request for hibernation, and to provide for a special execution path upon reboot after a power-cycle or some such, which would restore the registers. The question which OS was the first one to have that functionality still stands.
Leo B.
Feb 20, 2024 14:54
@trlkly What's your point? If the ability to do what you mention plus the ability to run a different OS in-between was available first, are you saying that is should not be called "hibernation"?
Leo B.
Feb 20, 2024 14:54
I don't get it. Which hardware provided saving state which could survive management running a higher priority job, you say? Aside: task checkpointing functionality provided by the OS was a thing; therefore it makes sense to ask who did it first. Dave's answer claiming that DEC RSX, or an earlier system, was capable of doing what I'm asking as an unintended way to pre-configure the system, looks more to the point to me.
Leo B.
Feb 20, 2024 14:54
@Raffzahn Then, naturally, the question might not apply to those systems. Also, when the question is "Was the feature present in operating systems", responding with "In the beginning there was no OS" is useless. Whether the feature was saving the state of the whole system or unloading running jobs, mentioning the OS version and the year range the feature was introduced would be expected for the answer to be acceptable.
Leo B.
Feb 20, 2024 14:54
@Raffzahn With removable disk packs, there was always a choice where to save the state of the system.
Leo B.
Feb 20, 2024 14:54
Having persistent memory does not help if maintenance involves replacing a part of it. Application-assisted checkpointing is out of the scope of the question.
Leo B.
Feb 20, 2024 14:54
@tofro With dual boot (Windows/Linux) PCs, it was possible to hibernate Windows, boot Linux, then return to the hibernated state in Windows.
 

 Discussion on question by texdr.aft: …

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Leo B.
Aug 1, 2022 15:26
Still, the answer is in the positive. See 4.2.2.3 of the Informal Introduction. A question formulated as "How were the calls to yet undeclared procedures handled in Algol-68 VW-grammar?" posted to CS.SE may be in order.
Leo B.
Aug 1, 2022 15:26
You can experiment with a standard-conforming compiler taken from jmvdveer.home.xs4all.nl/en.algol-68-genie.html
Leo B.
Aug 1, 2022 15:26
As asked, the question may be simply answered in the positive. Perhaps, in its intended phrasing it would better be suited for CS.SE.
Leo B.
Aug 1, 2022 15:26
You have not tried searching for "algol-68 mutual recursion", have you?
 

 Discussion on question by natevw: Whe…

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Leo B.
Jul 8, 2021 15:22
@alephzero Thank you! I was hoping that commercial ovens got electronic controllers earlier than the domestic ones. Alas.
Leo B.
Jul 8, 2021 15:22
When was the first microwave oven with electronic controls made?
 

 Discussion on question by StayOnTarge…

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Leo B.
Jul 3, 2021 17:39
@dan04 On UNIX, .p for Pascal is used as well.
 

 Discussion on question by Leo B.: Wha…

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Leo B.
Apr 8, 2021 17:31
@supercat Please see the updated question.
Leo B.
Apr 8, 2021 17:31
@WalterMitty Please see the updated question.
Leo B.
Apr 8, 2021 17:31
@berng I've corrected the wording.
 

 Discussion on answer by scruss: What …

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Leo B.
Oct 4, 2020 10:18
You beat me with the Elektronika BK answer.
 

 Discussion on question by Schezuk: Wh…

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Leo B.
Sep 13, 2020 17:24
@njuffa You're right, I rather meant the time when the trend started.
Leo B.
Sep 13, 2020 17:24
It is too tiresome to hand-optimize code for deeply pipelined superscalar processors; so, I'd say, since early 1990s when various Pentiums started to appear.
 

 Discussion on question by Leo B.: Wha…

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Leo B.
Feb 24, 2019 12:14
@shoover HP_2000_Contributed_Library_Rev_1638/Z905/LANDER close, but no cigar. :(
Leo B.
Feb 24, 2019 12:14
@shoover Indeed, HP-2000 sounds like a viable candidate! There also was a translated BESM-6 version of Star Trek which looked very much like the original HP-2000 version. Sadly, it hasn't survived.
Leo B.
Feb 24, 2019 12:14
@shoover Do you recognize the messages, or the gameplay in general?
Leo B.
Feb 24, 2019 12:14
@dirkt After 6 unsuccessful attempts the program terminates. No rotation ability there, and I've added the dump of all English messages to the question.
Leo B.
Feb 24, 2019 12:14
@manassehkatz Apparently the mainframe and minicomputer versions had split from the home computer ones (owing to different distribution channels?) and have diverged quite a lot. That makes me even more curious.
Leo B.
Feb 24, 2019 12:14
@UncleBod I'm curious about the provenance of the version which tracked the number of attempts. It spawned several translations after being brought to the USSR.
Leo B.
Feb 24, 2019 12:14
@WalterMitty I'm curious about the provenance of that version which tracked the number of attempts. I vaguely recall that there was another translation of the same English original, likely on a Soviet DEC clone, where "Turn in your spacesuit" was rendered as "Flights are over".
Leo B.
Feb 24, 2019 12:14
@Chenmunka In 1974, it would be around 4 years old, I guess?
 

 Discussion on answer by Raffzahn: Is …

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Leo B.
Dec 13, 2018 21:39
Let's not get ahead of ourselves with sound levels, background or motor noise, open/closed cover, etc. The first goal is to convert a time-stamped sequence of events like "print <line of text>" , "advance a line", "skip to end of page" into some kind a waveform with recognizable cadence, focusing just on the letter hammers and the line stepping mechanism.
 

 Discussion on answer by Leo B.: In MS…

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Leo B.
May 14, 2018 15:37
@jdv Not really: there is no jump into the middle of the loop.
Leo B.
May 14, 2018 15:37
@Raffzahn The semantics of one form is a subset of the semantics of the other, therefore the first form is necessarily faster than the second.
Leo B.
May 14, 2018 15:37
@MauryMarkowitz If memory serves, early implementations if BASIC did not have the NEXT form; the information about currently executing loops was kept in an array, and the NEXT var statement would find the increment, the bound and the location to jump to based on the variable name. At the last iteration the corresponding table entry would be discarded. The behavior we're discussing is the logical consequence of allowing NEXT while preserving backward compatibility.
Leo B.
May 14, 2018 15:37
@supercat Depends on the implementation. The Elektronika Basic worked much faster with integer variables.
Leo B.
May 14, 2018 15:37
@MauryMarkowitz It works like a combination of the C language's break for the inner loop and continue for the outer loop. I cannot think of a concrete example now, but I remember wishing for that in C a few times.
 

 Discussion on question by Leo B.: Wha…

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Leo B.
Apr 23, 2018 05:47
@SolarMike That will teach you to read questions completely.
Leo B.
Apr 23, 2018 05:47
@SolarMike The context was "as opposed to turning off echo completely".
Leo B.
Apr 23, 2018 05:47
@supercat A classic for sure. Reminds me of telling the password when prompting for it in Tolkien's "Speak, friend, and enter."
Leo B.
Apr 23, 2018 05:47
@rackandboneman It was not the OS, it was some MS-DOS application that used asterisks when entering a password. Maybe an encryption program, but I'm not sure.
Leo B.
Apr 23, 2018 05:47
@supercat That's crazy! And what would a terminal need a password for?
Leo B.
Apr 23, 2018 05:47
@Raffzahn I don't have an answer. I don't believe that MS-DOS had any influence on UNIX. My mention of MS-DOS was just an example. After all, it doesn't have any system programming interface for logins or password entry.