Recursive Computations in Spreadsheets
Jozef Hvoreck
No Email Address
Department of Mathematics
University of Papua New Guinea
Port Moresby
Papua New Guinea
Ivan Trencansk
ivo@euba.sk
Department of Applied Informatics
University of Economics
Bratislava
Slovakia
Abstract
In our contribution we would like to present two methods of implementation of recursive formulas in spreadsheets. The both methods use (rectangular) fields of cells for their computations.
The first method is "direct": Initial values (corresponding to trivial cases of recursion) are written in selected fields. Then, the recursive formula is written to other(s). Finally, the formula is spread along a necessary large area - until the required result is reached.
The second method allows to compute "recursive tables"- tables where the result of a two-argument recursive function is located on the intersection of the corresponding rows and columns. In this case each field in the area must contain the complete recursive formula. The computation is iterative - all values in the table are computed "simultaneously". Actually, the number of iterations equals to the maximum depth of recursion. Examples of such computations as well as sufficient conditions for the success of the method will also be presented.
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