\frac{2}{\left(\left(\frac{{t}^{3}}{\ell \cdot \ell} \cdot \sin k\right) \cdot \tan k\right) \cdot \left(\left(1 + {\left(\frac{k}{t}\right)}^{2}\right) + 1\right)}\begin{array}{l}
\mathbf{if}\;t \le -4.86000581215833313418115808157717702245 \cdot 10^{-239} \lor \neg \left(t \le 4.402616231627377082170896165667420584389 \cdot 10^{-246}\right):\\
\;\;\;\;\frac{2}{\left(\frac{\tan k}{\frac{\ell}{{\left(\sqrt[3]{t}\right)}^{3}}} \cdot \left(\left(1 + {\left(\frac{k}{t}\right)}^{2}\right) + 1\right)\right) \cdot \left({\left(\sqrt[3]{t}\right)}^{3} \cdot \left(\frac{{\left(\sqrt[3]{t}\right)}^{3}}{\ell} \cdot \sin k\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{2}{\frac{\left({\left(\sqrt[3]{t}\right)}^{3} \cdot \left(\frac{k \cdot t}{\ell} - \frac{1}{6} \cdot \frac{{k}^{3} \cdot t}{\ell}\right)\right) \cdot \tan k}{\frac{\ell}{{\left(\sqrt[3]{t}\right)}^{3}}} \cdot \left(\left(1 + {\left(\frac{k}{t}\right)}^{2}\right) + 1\right)}\\
\end{array}double f(double t, double l, double k) {
double r129952 = 2.0;
double r129953 = t;
double r129954 = 3.0;
double r129955 = pow(r129953, r129954);
double r129956 = l;
double r129957 = r129956 * r129956;
double r129958 = r129955 / r129957;
double r129959 = k;
double r129960 = sin(r129959);
double r129961 = r129958 * r129960;
double r129962 = tan(r129959);
double r129963 = r129961 * r129962;
double r129964 = 1.0;
double r129965 = r129959 / r129953;
double r129966 = pow(r129965, r129952);
double r129967 = r129964 + r129966;
double r129968 = r129967 + r129964;
double r129969 = r129963 * r129968;
double r129970 = r129952 / r129969;
return r129970;
}
double f(double t, double l, double k) {
double r129971 = t;
double r129972 = -4.860005812158333e-239;
bool r129973 = r129971 <= r129972;
double r129974 = 4.402616231627377e-246;
bool r129975 = r129971 <= r129974;
double r129976 = !r129975;
bool r129977 = r129973 || r129976;
double r129978 = 2.0;
double r129979 = k;
double r129980 = tan(r129979);
double r129981 = l;
double r129982 = cbrt(r129971);
double r129983 = 3.0;
double r129984 = pow(r129982, r129983);
double r129985 = r129981 / r129984;
double r129986 = r129980 / r129985;
double r129987 = 1.0;
double r129988 = r129979 / r129971;
double r129989 = pow(r129988, r129978);
double r129990 = r129987 + r129989;
double r129991 = r129990 + r129987;
double r129992 = r129986 * r129991;
double r129993 = r129984 / r129981;
double r129994 = sin(r129979);
double r129995 = r129993 * r129994;
double r129996 = r129984 * r129995;
double r129997 = r129992 * r129996;
double r129998 = r129978 / r129997;
double r129999 = r129979 * r129971;
double r130000 = r129999 / r129981;
double r130001 = 0.16666666666666666;
double r130002 = 3.0;
double r130003 = pow(r129979, r130002);
double r130004 = r130003 * r129971;
double r130005 = r130004 / r129981;
double r130006 = r130001 * r130005;
double r130007 = r130000 - r130006;
double r130008 = r129984 * r130007;
double r130009 = r130008 * r129980;
double r130010 = r130009 / r129985;
double r130011 = r130010 * r129991;
double r130012 = r129978 / r130011;
double r130013 = r129977 ? r129998 : r130012;
return r130013;
}



Bits error versus t



Bits error versus l



Bits error versus k
Results
if t < -4.860005812158333e-239 or 4.402616231627377e-246 < t Initial program 30.6
rmApplied add-cube-cbrt30.8
Applied unpow-prod-down30.8
Applied times-frac23.1
Applied associate-*l*21.2
rmApplied unpow-prod-down21.2
Applied associate-/l*15.5
rmApplied associate-*l/14.5
Applied associate-*l/13.0
rmApplied *-un-lft-identity13.0
Applied times-frac12.1
Applied associate-*l*10.4
if -4.860005812158333e-239 < t < 4.402616231627377e-246Initial program 64.0
rmApplied add-cube-cbrt64.0
Applied unpow-prod-down64.0
Applied times-frac64.0
Applied associate-*l*64.0
rmApplied unpow-prod-down64.0
Applied associate-/l*58.5
rmApplied associate-*l/58.5
Applied associate-*l/58.5
Taylor expanded around 0 43.6
Final simplification12.7
herbie shell --seed 2019325
(FPCore (t l k)
:name "Toniolo and Linder, Equation (10+)"
:precision binary64
(/ 2 (* (* (* (/ (pow t 3) (* l l)) (sin k)) (tan k)) (+ (+ 1 (pow (/ k t) 2)) 1))))