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 r8082 = 1.0;
        double r8083 = atan2(1.0, 0.0);
        double r8084 = 4.0;
        double r8085 = r8083 / r8084;
        double r8086 = r8082 / r8085;
        double r8087 = f;
        double r8088 = r8085 * r8087;
        double r8089 = exp(r8088);
        double r8090 = -r8088;
        double r8091 = exp(r8090);
        double r8092 = r8089 + r8091;
        double r8093 = r8089 - r8091;
        double r8094 = r8092 / r8093;
        double r8095 = log(r8094);
        double r8096 = r8086 * r8095;
        double r8097 = -r8096;
        return r8097;
}