48÷2(9+3) = ?

[olecapt]

Seen this one.

[Chachma v'Oz]

Beautiful!

[Ratbag]

No I'm not arguing. I can use google.
I'm just really amazed the I have never heard that before. I mean, its not like I'm a physics major or anything.

I'm in the boat with you jwreck, I'm not arguing that the left to right thing is wrong persay, but not heard it (at least not in the last 20 years) and there are other places in this thread where it is said multiply before divide etc (not going back to see who that was doiesn't matter) point being the internet is a strange place in that people will state things and whose word to take? obviously that demo has been taken from a source where's that from Charles? I'd like to think I've learned something from all this

[Malcolm Wright]

The problem I see here is that some people seem to be arguing from the point of view of immutable laws governing arithmetic.
However everything evolves, and I personally have gained from this thread that certain rules, such as the 'left to right' rule, would probably best be done away with. The proof is in the controversy - it is a rule which is failing. The practical goal is to avoid ambiguity, but if this rule which supposedly has been around for yonks, is not working because too few people are aware of it, or because it goes against reflexes instilled since the age of computer languages - we should trash it and either use parentheses to avoid any confusion, or align the direction of priority with syntactical evaluation (right to left).

This is simply common sense: no rule should be worth more than its practical value. Judging by the internet wide confusion - the left to right rule is under-performing.

When you learn a foreign language, don't you wish all those counter-intuitive irregularities had been swept away by rational minds, and replaced with ones that made sense? Languages evolve - might as well evolve them logically.

M.

[jwreck]

Well the best rule is "When in doubt, use parenthesis". If that rule is followed then there is no debate.

[jwreck]

Also, this is one of the things that I see that is the difference between math as it is taught, and math as it applies to reality. This is just an exercise in mental masturbation as it is presented. As it applies to reality, each number in the equasion would represent an actual value, and when solving the order of operation would be obvious.

[Malcolm Wright]

Also, this is one of the things that I see that is the difference between math as it is taught, and math as it applies to reality. This is just an exercise in mental masturbation as it is presented. As it applies to reality, each number in the equasion would represent an actual value, and when solving the order of operation would be obvious.

True - which makes Hitler's minions in the video even greater dunces

[caddis]

But it is. There are text books that state multiplication will be performed before division.

I'd like to have you prove this point

[caddis]

However everything evolves, and I personally have gained from this thread that certain rules, such as the 'left to right' rule, would probably best be done away with. The proof is in the controversy - it is a rule which is failing.

Lack of understanding of simple rules for operations does not make it a "controversy" It's absurd to take a system that works perfectly and logically simply because some don't understand it. Multiplication and division are inverse operations just like addition and subtraction...one isn't a higher order then the other. The real issue with the problem is using the division symbol...most mathematicians wouldn't write the problem like that, they would use a fraction bar. regardless, if you must write a problem out in a line then it's best to know what you are doing

[Malcolm Wright]

Lack of understanding of simple rules for operations does not make it a "controversy" It's absurd to take a system that works perfectly and logically simply because some don't understand it. Multiplication and division are inverse operations just like addition and subtraction...one isn't a higher order then the other. The real issue with the problem is using the division symbol...most mathematicians wouldn't write the problem like that, they would use a fraction bar. regardless, if you must write a problem out in a line then it's best to know what you are doing

You've failed to address half of my post.

It is far from absurd to tweak a system. It is not working perfectly well, as evidenced by the confusion that exists even amongst educated people.
Face it, it would be much clearer to tell people to always use parentheses in these cases. Problem solved.

M.

[caddis]

You've failed to address half of my post.

It is far from absurd to tweak a system. It is not working perfectly well, as evidenced by the confusion that exists even amongst educated people.
Face it, it would be much clearer to tell people to always use parentheses in these cases. Problem solved.

M.

You can use parenthesis any time you want, there is nothing that prevents someone from doing so, what you are asking for is redundancy.

[Malcolm Wright]

You can use parenthesis any time you want, there is nothing that prevents someone from doing so, what you are asking for is redundancy.

It is only considered redundancy for those who are aware of and keep in mind all the rules, and who do not have any conflicted impressions about said rules. Apparently that group is a minority.

For everyone else, it would be considered clarity rather than redundancy.

M.

[olecapt]

Also, this is one of the things that I see that is the difference between math as it is taught, and math as it applies to reality. This is just an exercise in mental masturbation as it is presented. As it applies to reality, each number in the equasion would represent an actual value, and when solving the order of operation would be obvious.

Nope.

If I had $10 for each software ambiguity error I have found in various code over the years I would be close to rich.

The ambiguity error is notorious. In fact there have been relatively small pieces of code in a number of places which people refused to touch because the actual operation performed was so optimized that touching any of it introduced ambiguity and related failure.

Formal testing of software has repeatedly failed. That is because we don't know how to catch the ambiguities.

And that is even in the the virtual domain where we don't have to deal with the problems of reality like hardware and its variance.

When I was a cub engineer some 45 years ago I established a reputation as an electronic wizard. That was based on the fact I made a minor logic change and fixed a problem that had been driving us nuts for months. What I actually did was find an ambiguity in our logic design and fixed it. For a few nanoseconds our logic system had an ambiguity. Mostly it worked right but rarely it did not. I blocked the ambiguity and the problem went away. No one ever saw it...nor could it be shown on the equipment of the time. But fix it and the problem vanished.

Ambiguity is hard stuff.

[olecapt]

I'd like to have you prove this point

OK - But that likely requires a half hour or more of effort.

Tell you what. I will do it if you agree to eat a guppie or the equivalent when I demand it in compensation.

How is that for a fair deal?

[jwreck]

Nope.

If I had $10 for each software ambiguity error I have found in various code over the years I would be close to rich.

The ambiguity error is notorious. In fact there have been relatively small pieces of code in a number of places which people refused to touch because the actual operation performed was so optimized that touching any of it introduced ambiguity and related failure.

Formal testing of software has repeatedly failed. That is because we don't know how to catch the ambiguities.

And that is even in the the virtual domain where we don't have to deal with the problems of reality like hardware and its variance.

When I was a cub engineer some 45 years ago I established a reputation as an electronic wizard. That was based on the fact I made a minor logic change and fixed a problem that had been driving us nuts for months. What I actually did was find an ambiguity in our logic design and fixed it. For a few nanoseconds our logic system had an ambiguity. Mostly it worked right but rarely it did not. I blocked the ambiguity and the problem went away. No one ever saw it...nor could it be shown on the equipment of the time. But fix it and the problem vanished.

Ambiguity is hard stuff.

Sounds like poor coding to me.

[olecapt]

Sounds like poor coding to me.

I don't doubt that. Most programmers never did figure out how time works.

Go back in history to the great IBM time sharing breakthrough. That is the famous system where the programmers believed they could spend 110% of real time doing overhead tasks. Did not work out well.

[Malcolm Wright]

Sounds like poor coding to me.

I'm not a coder by trade, but I'm pretty sure this kind of stuff can't be blamed on poor coding. Code gets piled upon code, used and repurposed and reused. During that process, something that never would have been considered a design flaw originally, can cause instability or wrong behavior. It just comes with the territory I think.

[jwreck]

I'm not a coder by trade, but I'm pretty sure this kind of stuff can't be blamed on poor coding. Code gets piled upon code, used and repurposed and reused. During that process, something that never would have been considered a design flaw originally, can cause instability or wrong behavior. It just comes with the territory I think.

That doesn't contradict my point. If the equasion has meaning, ie if the person writing the equation understands each term and what the equasion is trying to find, there is no reason at all it would be ambiguous.

[Malcolm Wright]

That doesn't contradict my point. If the equasion has meaning, ie if the person writing the equation understands each term and what the equasion is trying to find, there is no reason at all it would be ambiguous.

All I'm saying is that originally, a piece of code may not contain any ambiguity. But then integrated into a much larger edifice of code, something about its behavior may become ambiguous. The blame does not lie with the original coder but with someone who, along the way, failed to fully understand the repercussions of the behavior of that piece of code when fitting it into the larger program. But blame is a harsh word because it is very difficult to be fully aware of how hundreds of pieces of code are going to interact when assembled together into a larger whole. The process of developing large applications involves due diligence, but there are always a host of bugs - they are hunted down and in many cases fixed. Some bugs continue to elude repair and a cost/effect analysis often rules out expending any more energy on fixing them if they are intermittent and merely a hindrance rather than a blight.

[jwreck]

We're saying the same thing.

Or, I agree with you at least.