An enhanced four variables dataset for suggesting variable orderings for cylindrical algebraic decompositions

This dataset, named as DQ-4b, extends our previous four variables dataset DQ-4 published on science data bank (https://doi.org/10.57760/sciencedb.07989). It includes DQ-4 as a subset, but adds 2517 more difficult examples to enhance the quality of DQ-4. Like DQ-3 and DQ-4, it contains the running time and the number of cells of the CylindricalAlgebraicDecompose command in the RegularChains library of Maple under all possible variable orderings for 14317 randomly generated polynomial systems of four variables. For each example, the running time of the worst ordering is at least twice that of the best variable ordering. It can be used for benchmarking and designing heuristic methods and machine learning models for suggesting variable orderings for CADs. More information on the dataset can be found in readme.txt.