Efficient Implementation of ASTM E3076-18 Section 6.6

ASTM E3076, Standard Practice for Determination of the Slope in the Linear Region of a Test Record, Section 6.6, identifies the most linear portion of the test record. This step involves three levels of nested loops, each with a complexity that scales linearly with the number of points in the truncated normalized dataset. Due to the nested loops, this complexity can potentially incur hours or days of runtimes for large datasets. The present study demonstrates two methods of implementing Section 6.6 that are up to two orders of magnitude faster than a verbatim interpretation of ASTM E3076 while achieving identical results. A third method is presented that produces equivalent results, is fast, and has a runtime nearly independent of dataset length.