Re: Reason for operator precedence

In article <4416a498$1_4@xxxxxxxxxxxxxxxxxxxxxxxxx>,
Tony <ignorethis@xxxxxxxxxxx> wrote:
Hi all.

Hope this isn't a silly question.

I was wondering what the reason is for having multiple levels of operator
precedence?

So that polynomials and rational functions can be written
easily. That's essentially the main reason.

Phrased another way, why is it that we don't just evaluate everything from
left to right?

Having multiple levels of precedence obviously adds complexity, so I assume
there must be some payback. However, I don't see what it is.

So, by "evaluting left to right", I assume that you mean that
something like

2 + 3 * 5

would evaluate to 25, since 2 plus 3 is five, and then multiplying
that by 5 yields 25.

A general quadratic polynomial, using standard operator percedence, is
written as:

ax^2 + bx + c

And it can be written in other orders easily if you want:

c + bx + ax^2

bx + c + ax^2

etc.

How would you have to write it if you simply evaluated left to right?
The smallest number of parenthesis I can come up with is:

axx + (bx + c)

which may obscure the degree. If you want to put in the square, you
would need to do something like

bx + c + (a(x^2)).

Higher degree polynomials would be even harder.

--
======================================================================
"It's not denial. I'm just very selective about
what I accept as reality."
--- Calvin ("Calvin and Hobbes")
======================================================================

Arturo Magidin
magidin@xxxxxxxxxxxxxxxxx

.

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