Reverse Polish Notation in common use...

MacCaulay

Banned
...in my job, I do a lot of math. It's kind of needed, as you're machining shapes and determining locations in 3D and whatnot. In any case, I was talking to my dad (who was a machinist for 30 years before me) and he mentioned that he wasn't a fan of regular calculators as they used to much time.

"What did you use, then?" I asked, expecting him to say that he was faster when doing the math on paper.

"I had a calculator that did Reverse Polish Notation. The order of the numbers and signs is different, so you don't have to use parentheses."

So I looked it up, and it blew my freaking mind. Why people aren't using this I'm not sure, because it basically just seems so much easier to me.

So my challenge to you math and science folks is...Have Reverse Polish Notation in common use. And predict the effects!

Game on!
 
the main consequnce would be:
there are so many people typing the wrong keys on the calculators that Mathematicc coulf no more be considered an exact science
 
Er, what is it? Examples? I only know Chess Notation.

I didn't know what it was either, so I went on Google and looked it up. By making an active effort to educate myself on the subject, I found out the answer quicker than I would have done, had I instead relied on other people to inform me and advertising my unwillingness to independently research it.

EDIT: For example, it took twelve minutes for someone to post a reply informing you. It took 0.15 seconds for Google to direct me to a page full of useful topics, and roughly two minutes to gain a basic understanding.
 
It is still used to an extent

RPN exists as a part of Scientific Calculators, you can even download them as applications for your smartphone. The fact is though what seems to be more efficient for a typing interface ends up becoming just as cumbersome for button based calculation since there needs to be an "ENTER" key that needs to be hit every time you want to put in an additional variable before calculating. For those that are unfamiliar, it can just become downright confusing.

Hence since a majority of calculators rely on buttons so much for input rather then computing the raw text there is no real advantage until you want to do something useful with a particularly long number.

As for handwritten form it maybe easier to do in shorthand but its just easier to repeat symbols when teaching the basics, so they tend to stick.
 

MacCaulay

Banned
the main consequnce would be:
there are so many people typing the wrong keys on the calculators that Mathematicc coulf no more be considered an exact science

uh...what? That's stupid. You're typing less. Reverse Polish Notation takes away the need for parentheses.

Also, you're not even typing correctly now, so you're not exactly helping your argument.

Holy crap, this makes so much more sense than infix. Why don't we use this?

I know, right?
 

Ming777

Monthly Donor
It's a challenging way of doing things. It's used on some high end calculators. Course it's still taking a while to fully use the damn thing.
 
uh...what? That's stupid. You're typing less. Reverse Polish Notation takes away the need for parentheses.

Also, you're not even typing correctly now, so you're not exactly helping your argument.

I think he means all the people typing infix into postfix calculators and wondering why it's not working. But that's still dumb - I'd imagine people are fairly quick adapt to new standards quickly in a job where this might be implemented, because if you aren't then the boss will give the job to someone smarter.

Not to mention his implication that this has anything to do with mathematics as a science.
 

MacCaulay

Banned
For those of you who have brought up the inability of folks to learn a new way of writing mathematics, I'd point out that it seems that alot of machinists, pipefitters, applied scientists, etc., used RPN as a sort of mathematical-shorthand that was just as good as the real thing.

It's not hard to do: take a look at the wiki article for it, and in ten minutes you can be reasonably good at it.



Some people call that irony.
Not really sure of what it is, I think it is some sort of metal

And here I thought Irony was just a description of how my tap water tasted. :D
 
The problem is that standard (infix) notation is what is taught in schools. While I loved RPN, it required someone to actually understand what was going on. So, when Scientific calculators were used by Physics/Chemistry/Engineering majors (basically, people who have to understand calculus, and thus have demonstrated an ability to do more than rote memorization:)), it worked fine. When scientific calculators started being required by e.g. Grade 8 students.....

Besides, to a large extent, the purpose of computers is to make life easier for people. Requiring (most) people to learn a totally different method of entering calculations isn't 'easier'. (Of course, if you're doing such calculations on a regular basis, the ease of entry outweighs the difficulty of thinking differently.) In some ways, it's very like binary or hex. They make it a lot easier to work with computers - but have largely fallen by the wayside now.


Edit: not only is infix what is taught, it's how people think, by default. "2 and 2 is 4" is natural grammar/thought patterns (as compared to "2+2=4" which is it's mathematical formalization). People, in general, just don't think stack oriented. 2 2 + just doesn't make sense in any language I know.

(OK, German's pretty stack oriented, but that's with subordinate clauses...)
 
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It is fairly common, in fields that do lots of computation or work with computers a lot like computer science, engineering, physics, etc. It's just not used by most people, for the reasons Dathi said.
 
My trusty calculator that's carried me through a bachelor's degree in mechanical engineering dates from twenty, twenty-five years back, and it uses Reverse Polish Notation. It was my dad's, and I found it so convenient when I borrowed it in his Cal II class in high school that I never gave it back.
 
which is good till you want to add 32 + 11 ....... 3211+ = 44 or 322 or 214
Hence the "Enter" comment above. It separates the numbers.

@Dathi THorfinnson: What about "Senatus Populusque"? That sems to be at least one structure analogous to 2 2 +.
 
So my challenge to you math and science folks is...Have Reverse Polish Notation in common use. And predict the effects!
Game on!

Its funny, because the Algebra book we used in high school (Grade 10) had a chapter on RPN. The Teacher, of course, never got around to it. Me being curious, read up on it anyway. I thought at the time "Why would anyone want to do it?", but warmed up to it when I came across it later.

Consequences of the average human being using postfix/RPN?

The second program after "Hello World" would be to write a calculator in CS 101 classes because common familiarity with RPN makes it much easier.

Mathematics and science books/papers will be easier to typeset.

" G m1 * m2 * r 2 ^ / g = " is far simpler to print than its infix version.There will be butterflies on the typesetting industry. And there will be less of a need to develop TEX authoring programs.

And yes, the calculators will be more efficient.
 
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