Not an off-by-one error—at
least not in spirit. Interesting nonetheless.
I expected the article to eventually answer this puzzle:
> The competition started and got through a number of rounds. There were some comments about how the climber on the left always won.
Near the end:
> The kicker is that the out of place hold hasn’t been used in a long time. The climbers have optimised their route such that it is skipped. The same happens to the fourth hold from the bottom. So either being in the wrong place is immaterial to the climbers’ technique as long as they don’t get in the way.
So it seems like the error discovered by the article author should not have conferred any advantage to the climber on the left.
In terms of real-life off-by-one errors, it's hard to beat the town of Wemding in Bavaria (Germany).
Here a pyramid of 120 blocks is planned, with one placed every ten years. It started on the 1200th anniversary of the town, and is planned to be complete 1200 years later... and I'm sure you've spotted the problem.
If you cross your eyes and look at the routes as if it were a single stereoscopic image overlaying one route on top of each other, the misplaced hold jumps out at you immediately.
> If this were actual code review the correct comment would be something like “this [piece] hasn’t been used for years, it should be deleted”. But this is something in physical space, and there would be arguments that removing it (them) means the route has changed, thus times are no longer comparable.
Hmm, I think the correct analogy is rather a benchmark. Like code in a benchmarking tool or test, the whole climbing course does not serve any purpose, any actual goal, except to be completed as fast as possible.
You wouldn't say "these instructions should be deleted because branch prediction and speculative execution in recent years have made it so that total cycle count is the same without them", for the reason stated ultimately after in the article already: That may not have been true in the past, and may change again in the future.
I discovered an off-by-one error in college as I was graduating. Apparently the "class plan" I had put together with an advisor during my second year was missing a class, and I discovered it as I petitioned it for graduation. "You're one class short."
(It was for my second major, not the primary one, and the head of the physics department was nice enough to credit a nonlinear optimization course from engineering toward the major, so I earned it.)
AEVL ·5 days ago
I expected the article to eventually answer this puzzle:
> The competition started and got through a number of rounds. There were some comments about how the climber on the left always won.
Near the end:
> The kicker is that the out of place hold hasn’t been used in a long time. The climbers have optimised their route such that it is skipped. The same happens to the fourth hold from the bottom. So either being in the wrong place is immaterial to the climbers’ technique as long as they don’t get in the way.
So it seems like the error discovered by the article author should not have conferred any advantage to the climber on the left.
Anyone who can shine light on this matter?
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NeoTar ·5 days ago
Here a pyramid of 120 blocks is planned, with one placed every ten years. It started on the 1200th anniversary of the town, and is planned to be complete 1200 years later... and I'm sure you've spotted the problem.
Matt Parker, the 'stand-up Mathematician' has a video on it: https://youtu.be/FAdmpAZTH_M?si=_u8fM-fprUWiEqZ9
delgaudm ·5 days ago
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anyfoo ·5 days ago
One comment on what the article says:
> If this were actual code review the correct comment would be something like “this [piece] hasn’t been used for years, it should be deleted”. But this is something in physical space, and there would be arguments that removing it (them) means the route has changed, thus times are no longer comparable.
Hmm, I think the correct analogy is rather a benchmark. Like code in a benchmarking tool or test, the whole climbing course does not serve any purpose, any actual goal, except to be completed as fast as possible.
You wouldn't say "these instructions should be deleted because branch prediction and speculative execution in recent years have made it so that total cycle count is the same without them", for the reason stated ultimately after in the article already: That may not have been true in the past, and may change again in the future.
Show replies
philip1209 ·5 days ago
I discovered an off-by-one error in college as I was graduating. Apparently the "class plan" I had put together with an advisor during my second year was missing a class, and I discovered it as I petitioned it for graduation. "You're one class short."
(It was for my second major, not the primary one, and the head of the physics department was nice enough to credit a nonlinear optimization course from engineering toward the major, so I earned it.)
Show replies