Calculate the Date of Easter

The book "Calendar," by David Ewing Duncan, contains an elaborate algorithm for the computation of the date of Easter in any year. Not only does the algorithm have to take into account the spring equinox but it also has to avoid making Easter fall on the same date as the Jewish Passover. David Duncan presents the formula in print.

Here is the algorithm translated into a Solver equation. The equation may not be the most efficient way to solve the problem but it conforms to the original algorithm in all its gory details.

The formula was tested for about 15 or 20 different years and it worked well. I used the following URL on the World Wide Web to check the results of the formula against another person's computations. All of the results from the Web site matched those from the Solver equation.

www.smart.net/~mmontes/ec-cal.html

Anyway, here is the equation (box at right). The first part between the two exclamation points is an extended comment. This part does not need to be keyed into the Solver editor. I like to have these comments along with the actual equation. It makes it easier to find the source.

Avi Meshar: http://www.dasoft.com

Editor: Please check the above site for the most recent version of the Easter equation.