compute half life with only two data points

[slyrus]

It would be nice if one could compute a half-life from only two points.

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This works:

PKNCA::pk.calc.half.life(conc=c(1, 0.5, 0.25),
                         time=c(0, 1, 2),
                         min.hl.points=3,
                         allow.tmax.in.half.life=TRUE,
                         check=FALSE)

but this doesn't:

PKNCA::pk.calc.half.life(conc=c(1, 0.5),
                         time=c(0, 1),
                         min.hl.points=2,
                         allow.tmax.in.half.life=TRUE,
                         check=FALSE)

[billdenney]

Thank you for pointing this out. I just fixed it.

The underlying issue had to do with the fact that adjusted r-squared requires 3 points for calculation. Now adjusted r-squared with 2 points or fewer is NA instead of an error.