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diff --git a/src/Coxeter_triangulation/include/gudhi/Functions/Function_lemniscate_revolution_in_R3.h b/src/Coxeter_triangulation/include/gudhi/Functions/Function_lemniscate_revolution_in_R3.h
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+/*    This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
+ *    See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
+ *    Author(s):       Siargey Kachanovich
+ *
+ *    Copyright (C) 2019 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef FUNCTIONS_FUNCTION_LEMNISCATE_REVOLUTION_IN_R3_H_
+#define FUNCTIONS_FUNCTION_LEMNISCATE_REVOLUTION_IN_R3_H_
+
+#include <cstdlib>  // for std::size_t
+#include <cmath>    // for std::sqrt
+
+#include <Eigen/Dense>
+
+namespace Gudhi {
+
+namespace coxeter_triangulation {
+
+/**
+ * \class Function_lemniscate_revolution_in_R3
+ * \brief A class that encodes the function, the zero-set of which is a surface of revolution
+ * around the x axis based on the lemniscate of Bernoulli embedded in R^3.
+ */
+struct Function_lemniscate_revolution_in_R3 {
+  /**
+   * \brief Value of the function at a specified point.
+   * @param[in] p The input point. The dimension needs to coincide with the ambient dimension.
+   */
+  Eigen::VectorXd operator()(const Eigen::VectorXd& p) const {
+    double x = p(0) - off_[0], y = p(1) - off_[1], z = p(2) - off_[2];
+    Eigen::VectorXd result(cod_d());
+    double x2 = x * x, y2 = y * y, z2 = z * z, a2 = a_ * a_;
+    double t1 = x2 + y2 + z2;
+    result(0) = t1 * t1 - 2 * a2 * (x2 - y2 - z2);
+    return result;
+  }
+
+  /** \brief Returns the (ambient) domain dimension.*/
+  std::size_t amb_d() const { return 3; };
+
+  /** \brief Returns the codomain dimension. */
+  std::size_t cod_d() const { return 1; };
+
+  /** \brief Returns a point on the surface. This seed point is only one of
+   * two necessary seed points for the manifold tracing algorithm.
+   * See the method seed2() for the other point.
+   */
+  Eigen::VectorXd seed() const {
+    Eigen::Vector3d result(std::sqrt(2 * a_) + off_[0], off_[1], off_[2]);
+    return result;
+  }
+
+  /** \brief Returns a point on the surface. This seed point is only one of
+   * two necessary seed points for the manifold tracing algorithm.
+   * See the method seed() for the other point.
+   */
+  Eigen::VectorXd seed2() const {
+    Eigen::Vector3d result(-std::sqrt(2 * a_) + off_[0], off_[1], off_[2]);
+    return result;
+  }
+
+  /**
+   * \brief Constructor of the function that defines a surface of revolution
+   * around the x axis based on the lemniscate of Bernoulli embedded in R^3.
+   *
+   * @param[in] a A numerical parameter.
+   * @param[in] off Offset vector.
+   */
+  Function_lemniscate_revolution_in_R3(double a = 1, Eigen::Vector3d off = Eigen::Vector3d::Zero())
+      : a_(a), off_(off) {}
+
+ private:
+  double a_;
+  Eigen::Vector3d off_;
+};
+
+}  // namespace coxeter_triangulation
+
+}  // namespace Gudhi
+
+#endif