Generating Grid Cell Values based on other values.

How to make the data grid view populate with inverse of the filled values at a given cell?

I want to do the following.

 

For example I have a grid of equal size which is n rows and n columns like below:

 

For instance lets take 4 * 4 grid here

 

Factor     a     b     c     d

a             1

b                    1

c                           1

d                                 1

 

All the diagonal values are by default 1 and I already wrote the code for that.

 

So, now for example I click on the cell row[b] column[a] and enter value 3 in it, now if I click on a different cell immediately after that, I would like to have the opposite order row[a] column[b] cell value to be filled with the inverse (1/3) of the earlier filled values. This process should happen either way. Whenever a cell value is filled in the upper half or lower half matrix the exact opposite cell value should be having an inverse value. I would like to do this for n*n matrix because here n is coming out as a count value from a different method.

 

Can any one help me out in doing this please.