Excel 2013 ... @...???

[Bromance]

So, I am taking an advanced Office course in college. We are currently working in Excel.
I missed a submission on the online homework site, yet my formula seemed correct and yielded the appropriate result.
I asked my instructor what was wrong with my formula and he told me to use the "@" symbol and learn what it does...
So far, I do not know what it does and Google is yielding literally no results (not to mention our course book doesn't mention it).

Background info on homework:
I was working in data tables and structured formulas. The formula I was using was VLOOKUP.
For some reason, when I referenced the table as =VLOOKUP(Table[Column_Name....]) it yielded the right result. But I had to put =VLOOKUP(Table[@[Column_Name...]]).

So, what is the difference between using the "@" symbol and not using it?
Under what circumstances would you use one or the other?

Thanks for taking the time!

[macropod]

There was nothing wrong with your formula. In 30 years of using Excel, I've never encountered the @ as something required in any Excel formula, unless it was part of something being tested. Mind you, I generally prefer to an INDEX/MATCH combination instead of VLOOKUP because INDEX/MATCH works with unsorted data.

AFAIK, the @ is a compatibility option left over from the days of Lotus 123, which did require it. Excel allows the @ but does not require it and it adds nothing to what you already had, except clutter. If the Lotus compatibility character is what it is and this is supposed to have been an Office course, your instructor was wrong.

If your instructor is going to tell you you're wrong, challenge him to produce an example where it does make a difference, and a reference to it. Simply telling you to "learn what it does" without providing any relevant material is unreasonable.

Even Microsoft's documentation makes no mention of it. See:
http://office.microsoft.com/en-au/ex...010343011.aspx
https://support.office.com/en-US/Art...rs=en-US&ad=US
http://msdn.microsoft.com/en-us/libr...ffice.12).aspx

FWIW, IBM - the owner of Lotus 123 - doesn't even sell or support it any more. The last release of Lotus 123 was version 5 ... in 1994!

[gebobs]

When making formulas using table automation, Excel puts the @ symbols in automatically. Sometimes, they aren't necessary and if you take them out, the formula returns the same result. Other times, not so much.

It seems to me is what it's saying is: take the cell in this row (i.e. the same one as the formula is in) @ this column and do some operation with another cell @ this column.

e.g. =([@Widgets]-[@Flanges])/[@Flayrods]

If Widgets are in A, Flanges in B, Flayrods in C, that is how the equation would appear if you enter the formula in D2 and clicked the cells in A2, B2, and C2 to generate it.

I can take out the @ symbols and the equation works fine.

=([Widgets]-[Flanges])/[Flayrods]

However, if I do a sum of the same columns, the equation appears as:

=SUM(Parts[@[Widgets]:[Flayrods]])

Take out the @ symbol, and the formula returns a #REF! error.