Function moment2st() solves the
location \(\xi\), scale \(\omega\), slant \(\alpha\)
and degree of freedom \(\nu\) parameters of skew-\(t\) distribution,
from user-specified mean \(\mu\) (default 0), standard deviation \(\sigma\) (default 1),
skewness and kurtosis.
An educational and demonstration function moment2t_demo solves
\((\omega, \nu)\) parameters of \(t\)-distribution,
from user-specified \(\sigma\) and kurtosis.
This is a non-skewed distribution, thus
the location parameter \(\xi=\mu=0\), and the slant parameter \(\alpha=0\).