What Is a Nomogram? | Hacker News Reader

What Is a Nomogram?

lefakkomies.github.io

124 pointsyummypaint23 comments

I use my E6-B flight computer [1] every time I fly. Is it a nomogram or a slide rule? I think it is both! It is such an amazing useful calculator. At the flight school I went to, it was common for students who got their instrument rating to buy a nice GPS. I got a nice metal E6-B as my plastic one was showing some wear and tear. There is something really cool about instrument flying with a E6-B, and navigating using VOR/DME/TACAN and dialing in the ILS and getting on the glide slope.

https://en.wikipedia.org/wiki/E6B

Interesting! Wikipedia says that E6B is "one of the very few analog calculating devices in widespread use in the 21st century". What are those other few?

Does an abacus count? (heh)

Oh, also: old timey cash registers, though they're _rare_.

I'd consider both abacus and a mechanical cash register (or even mechanical arithmometer) as digital/discrete devices, not analog; analog calculation would refer to slide rules, nomograms and the like (of which I'm sure there would be more than the slide rules and nomograms, but nothing comes to mind..).

Yeah, on thinking about it, seems like you're right.

Too bad, I can no longer think of any then. I think ballistic computers were at one point analog, but those should all be obsoleted now.

Seems like a lot of machining -- creating threads and the like -- is done with mechanical calculating devices.

My understanding is that the “Wulff net” is still used in geology, though nowadays computers probably do most of the plotting.

If anyone has a chance, I can heartily recommend a visit to the Arithmeum in Bonn. It is a museum of calulation/calculators not only situated in a beautiful building, but also home to many fine and sometimes interactive manual / mechanical calculation devices. Some discrete, but it also houses the world's largest collection of sliderules. There were tons which had very specific usage, e.g. in farming. No clue which are still being used today, but I bet plenty still are.

https://www.arithmeum.uni-bonn.de/en/arithmeum.html

I use a slide rule similar to the E6B for calculating feeds and speeds to run a milling machine.

Some manufactures used to give away promotional slide rules, like the capacitor company would send you one that lets you calculate the right size of capacitor for your application.

The calculator side is a circular slide rule. The wind correction side with the sliding plate is a nomogram.

https://www.gleimaviation.com/e6b-flight-computer-instructio...

But aren't slide rules themselves nomograms?

Project Rho has a bunch about nomograms at http://www.projectrho.com/nomogram/index.html .

One example, at http://www.projectrho.com/public_html/rocket/engines.php#nom... , is a Delta-V Nomogram for the solar system. Given your exhaust velocity and mass-fraction you can compute your delta-V, and combinations thereof.

The last time I saw a physical one (ie, "in real life") was on a booklet for parents of newborns. It estimated the child's predicted height based on the heights of the parents.

I have a copy of Svoboda's work "3 bar linkage computers" from the MIT radiation labs series.

https://www.randomwraith.com/documents/Svoboda-ComputingMech... (different edition to mine)

Probably not identical. but the kid next door? Svoboda worked on nomograms too from google searches.

(I think the linkage computers were used in gunnery, and in ground-controlled-radar and like, before computing went digital)

I would love to see Corey Quinn from Duckbill (https://twitter.com/QuinnyPig) make one of these for S3 pricing. How much are you storing, how much egress and shoot out a dollar value.

Then do it for other vendors.

First time I stumbled over Nomograms (or rather 'Nomographs' as they're called there) was a few years ago in the Silent Hunter 5 uboat simulation. It's part of the navigation map tools and used to quickly lookup speed, time or distance from the two other (observed or estimated) values, usually for dead reckoning of surface ship locations. Lot's of other interesting and educational stuff in that game, like a handful of other "mechanical" navigation tools, and a proper Enigma emulation (this is implemented in a mod though).

A cool nomogram from statistics available here https://bmcmedresmethodol.biomedcentral.com/articles/10.1186... people often confuse the p-value as posterior probability of the null hypothesis. With this nomogram it is possible to compute a bound on the actual probability of the null hypothesis based on a specified prior and p-value.

Trolling old electronics magazines from the 1950's or so I would encounter nomograms to compute various electrical properties. Seems like a cool use.

I wanted a nomogram to compute volume from l x w x h to make fast work in calculating speaker dimensions but spent only a passing amount of time trying to create one. The point of the nomogram for volume was so that I could compute one of the lengths based on a pre-determined cabinet volume I wanted and two of the other lengths.

Somewhat related: I created a kind of "digital slide rule" with logarithmic scales and all for an iOS app that computes Ohm's Law. It is so much more fun to play with then typing numbers into text fields and having the software compute the result. I think that is the appeal with nomograms for me as well, you can just real-time play with numbers in an interactive way. Not "turn based" like text fields.

Old electronics magazines here: https://worldradiohistory.com/Popular-Electronics-Guide.htm

Ohm's law with sliding rules: https://apps.apple.com/ec/app/perfboard/id465951871?l=en

It's curious to see the word nomogram surfacing again (at least in this context). I stopped using it after I realized that people didn't understand what I was talking about.

I can't remember how I came by the word except it was commonplace to see in textbooks and references when referring to diagrams/tables/charts combinations. For example, a diagrammatic representation of sliderule scales etc. in a textbook would have a comment to the effect 'the monograph in figure (a) illustrates the results/correlation of...' etc.

Nomogram's use in technical references has never struck me as strange, in fact it's the appropriate word to use when making such references. Thus it'd be interesting to know why the word has fallen out of favor in recent years.

Edit: I don't think the use of calculators is the full reason the word has fallen out of favor as we've more graphic representations of data as the consequence of computers now than before. It seems to me it's possible that the word has dropped out of favor with the less formal more simplified language used in texts these days.

I think it's because there isn't a need for a catch-all word. If it's a plot/chart style of nomogram, for example, we just call it a plot or a chart. I never need to convey the general idea of graphical computation. I do think it's related to the prevalence of computers.

If you like nomograms, you might also like the Nomographer YouTube channel.

https://youtube.com/channel/UCOLYtsL4ge6QfaAvBDeG1IA

For general avaiation aircraft, takeoff and landing distance computation is frequently performed using nomograms published in the Approved Flight Manual or Pilot's Operating Handbook.

https://math.stackexchange.com/questions/2537922/translate-p...

The subdomain in the url is the Finnish word for ’batman’ with the consonant ’p’ replaced with ’f’ for an unknown reason. Just sayin’.

You can use a nomogram to very elegantly summarize a logistic regression model (really, any additive model)

For example: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6152514/