Syntax: @COL(C)
C = a cell or range (optional)
@COL returns the column index of the cell referenced by C, or the left-most column if C is a range, or the column in which the formula appears if C is omitted.
Examples:
@COL(A1) = 0
@COL(F10..G19) = 5
@COL = 25, where @COL is in cell Z20.