Known bug in Excel????

[mortgageman]

According to math rules 2^3^2 should equal 2^9 (you go right to left in this case). Excel gives 64. Is this a known bug?

Gene Klein

 

[cummingsea]

"The question at issue is whether to interpret 2^3^2 when used in an Excel expression as..."

When used in an Excel expression, 2^3^2 must be interpreted as 64 or one will get errors. There is no question about it.

Its not a question of right or wrong notation, its what gets the correct solution.

"Why does =2^3^2 return 64?" is similar to "Why is the formula =(1=1)OR(1<>1) rejected by Excel?"

You say that Excel rejects +(1=1) returns TRUE in Excel Mac 2011, and for =(1<>1) returns FALSE in Excel Mac 2011. I am not questing you, I am just wondering if Excel on an Windows machine gives a different answer. Thanks for your reply in advance.

 

[shg]

Same result on PC.

 

[trunten]

I do agree that excels rules for this differ from those we learnt in maths classes. But what would you answer be to the following two sentences

What is the answer of 2 to the power 3 (pause) to the power 2

What is the answer of 2 to the power (pause) 3 to the power 2

I think that's probably at the heart of what excel does here. Most people that use excel probably don't remember too much past BODMAS so excel kept it simple. Was this right or wrong? I would say wrong but once you find out excel behaves this way it's not too difficult to add a couple of parentheses.

Anyway maths isn't always sensible to "outsiders".

http://xkcd.com/179/

 

[shg]

I don't know of any notation that includes pauses. It would be unambiguous if you used parens.

 

[Norie]

What's BODMAS?

 

[trunten]

I don't know of any notation that includes pauses. It would be unambiguous if you used parens.

Are you being serious?

I was trying to express how one might ask the question. Depending on where a pause lies questions take on different meaning.

What is the answer of 2 to the power 3, to the power 2

What is the answer of 2 to the power, 3 to the power 2

Happier?

 

[trunten]

What's BODMAS?

It's a scale body builders use to determine how "ripped" they are.

edit:
Just in case you weren't joking. It's an acronym taught to children (at least in Birmingham! Probably the whole of the uk) in year 7 to remember the order of precedence in maths

Brackets
Other (or sometimes pOwers)
Division
Multiplication
Addition
Subtraction

 

[shg]

I would add commas to pauses. Maybe "air quotes" would be a good addition to your system.

Notation was invented (relatively late in the development of mathematics) to avoid the ambiguities of narrative descriptions of expressions.

 

[trunten]

I would add commas to pauses. Maybe "air quotes" would be a good addition to your system.

Notation was invented (relatively late in the development of mathematics) to avoid the ambiguities of narrative descriptions of expressions.

Agree completely with you. But like i said MS probably had a discussion around what an average user would expect. As most people work from left to right they chose their way. I think that's wrong to be honest, but I can live with it.

 

[shg]

Simple

and

unambiguous

. Who could ask for more?