One of the basics of Excel is that I can define a cell's contents by creating
a formula in that cell that links to another cell. For example, I can enter
the formula =A5 into cell A1 and A1 would then be equal to whatever is in A5.

This works great. However, I would like to do the opposite. I would like to
define another cell's contents by creating a formula in the current cell.
For example, I would set cell A5 equal to say "nnn" by entering a formula
into cell A1. That is, cell A1 would modify an external cell A5.

Is this possible using Excel's basic formulas or would I have to use VBA?
Moreover, can I automatically run a VBA macro from a cell, in pretty much the
same way that say the formula =SUM() automatically runs?

I would appreciate any advice. Thanks.

No, one cell cannot change another cell's contents without VBA.

To change A5 based on what's in A1, you need to enter the formula in A1.
Something like:

=if(a1="test","nnn","not nnn")

You cannot get a cell to run a macro. However, you can create your own
functions. So instead of using =Sum(...), you can say =Mysum(...), and then
create the function Mysum in VBA.

--
Regards,
Fred


"HandsomeJake" wrote in message
...
One of the basics of Excel is that I can define a cell's contents by creating
a formula in that cell that links to another cell. For example, I can enter
the formula =A5 into cell A1 and A1 would then be equal to whatever is in A5.

This works great. However, I would like to do the opposite. I would like to
define another cell's contents by creating a formula in the current cell.
For example, I would set cell A5 equal to say "nnn" by entering a formula
into cell A1. That is, cell A1 would modify an external cell A5.

Is this possible using Excel's basic formulas or would I have to use VBA?
Moreover, can I automatically run a VBA macro from a cell, in pretty much the
same way that say the formula =SUM() automatically runs?

I would appreciate any advice. Thanks.