Let's imagine I have the following table structure
data = {{a, b}, {c, d}, {e, f}};
and I want to transform it into the following table
dataEdited = {{a, (f[a] + f[b])/f[a]}, {c, (f[c] + f[d])/f[c]}, ...}
by leaving the first column unchanged and applying a function to the second column which also involves the first column.
My attempt is to apply MapAt to the second column, but I don't know how I can access the first column in this way. In the small example below I just apply the sine function to the second column.
data = {{a, b}, {c, d}, {e, f}};
dataEdited = Transpose[MapAt[Sin /@ #1 &, Transpose[data], 2]];
Any ideas or "best practice" recommendations how to handle this kind of operations?