Quote: Originally posted by Maverick on January 18, 2005
About the numbers that originally appear on the left side going downwards, can I delete the numbers and put in my own numbers or letters? Same question for the original letters that appear on top going across.
the original numbers and letters are the cell address components, the alpha portion = column and the numeric portion = row... for example, column C is the third one over, row 5 is the fifth one down, cell C5 is 3 over and 5 down... this is known as cell addressing and is the basis for excel so they cannot be changed.
here is a simple intro to the basics of cell addressing and formula creation...
in the first cell (A1) type 9
in the cell below that one (A2) type 3
in the cell below that type =A1-A2
once you hit enter, the =A1-A2 calculates the result, 6
now here is where the fun and power of excel kick in... in cell A1, change the 9 to a 12
the formula is using cell addressing rather than fixed numbers, so it automatically changes to reflect the new data.
Forgive me if that sounded too basic, but addressing is the key to much more complex formulas later on....
now step 2, absolute versus relative addressing...
in your example file, in cell B1, put a 5, then in C1 put a 7
in cell B2 put a 1 and in cell C2 put a 4
now, move the mouse to the bottom right corner of cell A3, you have it right when the pointer changes to a + . now drag it over to cell C3... note how all the right answers are under the right columns? that's the power of "autofill". note the formulas in each of the 3 cells in row 3 have changed themselves to =B1-B2 and =C1-C2, respectively?
that's a relative address... it's like saying... make a left 2 stoplights from city hall... how many towns would those instructions work in?
an Absolute address is an exact cell reference, this will NOT change even if you autofill the formula, it's like saying 123 main street, anytown, CA, 90210.... it specifies an exact place.
let's work that in to the example.... in cell D1, enter a 10
now, in cell A3, modify the formula to the following... =A1-A2+$D$1
The dollar signs act as anchors, they will not change.... now autofill this to cell C3... and look at the formula as it appears in cell B3, it is now =B1-B2+$D$1
the value in D1 here represents a constant.... if you were calculating sales figures, this could represent a tax rate.
if you only typed =A1-A2+D$1, then the D would change in relation to that cell, now B3 would read =B1-B2+E$1 (E1 is blank).
each scenario can be used to your advantage once you understand the difference. just think of the $ as an anchor and you'll be fine ;-)
but that is why you can't change the numbers and letters along the side... (you CAN hide them, but that's another story altogether...