A practical algorithm for the computation of tree felling times

Abstract

The time taken for a tree to fall when felled can be expressed in closed form in terms of elliptic integrals. However, this form of the solution is of limited practical use to the non-mathematician. A straightforward numerical method is presented that can be programmed into a spreadsheet in a few lines without requiring any high level programming or mathematical skills. Good accuracy for practical purposes is obtained without any iteration, but accuracy is further improved with two or three iterations, each involving only one or two extra cells in the spreadsheet. Results are compared with the analytic solution. This article demonstrates how a challenging real problem is accurately solved numerically with basic office tools and limited mathematics. References

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