code 41762;
real procedure STUDENTDENS(X, DF);
value X, DF; real X, DF;
STUDENTDENS:= if DF ≤ 0
              then STATAL3 ERROR(“STUDENTDENS”, 2, DF)
                    else
                    EXP(LOGGAMMA((DF + 1) / 2) - LOGGAMMA(DF / 2) -
                     (DF + 1) / 2 × LN(1 + X × X / DF) -
                      LN(DF) / 2 - .57236494299247);
eop