is
fun isFeasibleSPT(lowerQuantile: Double, median: Double, upperQuantile: Double, alpha: Double = DEFAULT_ALPHA, lowerBound: Double = Double.NEGATIVE_INFINITY, upperBound: Double = Double.POSITIVE_INFINITY): Boolean(source)
Whether the supplied symmetric percentile triplet describes a valid three-term metalog, checked without constructing one. This is the closed-form feasibility condition of Keelin (2016) Proposition 2, expressed through the coefficients the triplet produces.