phScaleCL(ph, a1, a2)  returns the clearance‐scaling factor associated
    with the combined genotype a1/a2 and phenotype ph by:
phStatus(ph,a1,a2) to get a MetabolizerStatus.ph.CLscale vector at that status (converted to an integer).ph – A Phenotype record with fields:
           poor, intermediate, rapid, and
           a CLscale array of length six.a1, a2 – Star‐allele strings.f – Real factor (e.g. 0.85) to multiply the
           nominal clearance.function phScaleCL input PGx.Phenotype ph; input String a1; input String a2; output Real f; end phScaleCL;