A Simple Method for Doing Repeated Complex Multiplications in Excel

  One can use the drag and fill method to do repeated complex multiplications in Excel. After entering data for the pointer p and complex numbers a and b saved as 2-vectors one enters the first formula into upper left cell of the product range. One then clicks on the square box at the lower left of the cell with the left mouse button, drags it down one row and releases the button. One again clicks on the button with both cell selected and drags it to the right to fill the remaining column. Note that only the column of b is not fixed in the formuls to allow for drag and fill down and to the right.

Here's the VBA code for the user function cMult(a,b,p):

Note well that the indices for the ranges of a and b start at 1 so it would be best if the values of the pointer corresponded to this count. One needs to be careful about exceeding the bounds of the range but this should be considered an Excel user responsibility. Don't forget one can use the undo button to backstep worksheet entries and undo mistakes.