Cannot sample enough valid points. (more)

\[-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right)\]
-\frac{1}{\frac{\pi}{4}} \cdot \log \left(\frac{e^{\frac{\pi}{4} \cdot f} + e^{-\frac{\pi}{4} \cdot f}}{e^{\frac{\pi}{4} \cdot f} - e^{-\frac{\pi}{4} \cdot f}}\right)
double f(double f) {
        double r7986 = 1.0;
        double r7987 = atan2(1.0, 0.0);
        double r7988 = 4.0;
        double r7989 = r7987 / r7988;
        double r7990 = r7986 / r7989;
        double r7991 = f;
        double r7992 = r7989 * r7991;
        double r7993 = exp(r7992);
        double r7994 = -r7992;
        double r7995 = exp(r7994);
        double r7996 = r7993 + r7995;
        double r7997 = r7993 - r7995;
        double r7998 = r7996 / r7997;
        double r7999 = log(r7998);
        double r8000 = r7990 * r7999;
        double r8001 = -r8000;
        return r8001;
}