Excel Order of Operations

[Irontrussman]

I was browsing through the threads and came across a warning, and ensuing discussion (thread404-157296), on whether Excel should calculate the expression -5^2 as equal to 25 or -25. If you use the Excel function Power(number,power) then there is no ambiguity. If you want to square -5 then you would enter, =Power(-5,2). If you want to negate the square of 5, then you would enter =-power(5,2).

 

[dvd]

I think that only applies in base 10.

 

[handleman]

The Power method is no different from proper use of parenthesis except that it takes five additional keystrokes. =Power(-5,2) does exactly the same thing as (-5)^2, and =-Power(5,2) does exactly the same thing as -(5^2). That is, it forces Excel to evaluate in the order you want.

-handleman, CSWP (The new, easy test)

 

[electricpete]

.. on whether Excel should calculate the expression -5^2 as equal to 25 or -25

So which was it? ;-)

The Power method is no different from proper use of parenthesis except that it takes five additional keystrokes.

Lol. Good point.

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[IceStationZebra]

It equals 25. -5^2 = (-5)^2 not -1 x (5^2)

And as far as operation order, if you remember your high school math class in the absence of parenthesis the equation should be computed by taking powers/squares first, then multiply/divide, and lastly add/subtract.

ISZ

 

[handleman]

Please, let's not get into that argument here. It was sufficiently addressed (thrashed to death) in the referenced thread.

-handleman, CSWP (The new, easy test)

 

[SomptingGuy]

Any engineer using Excel for real work deserves all the ambiguities it throws at them.

As hammers go, Excel isn't a good one.

- Steve

 

[sailoday28]

IceStationZebra (Mechanical) 18 Sep 08 22:49
It equals 25. -5^2 = (-5)^2 not -1 x (5^2)

No way! It equals -25. -5^2 = -(5)^2 = -1 x (5^2)
Check any algebra book.

Regards

 

[vpl]

This thread is merely repeating the arguments that were in thread404-157296.

The end conclusion in that thread was: use parentheses so you get the answer you expect.

Patricia Lougheed

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