lm_fit.hpp 2.71 KB
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#pragma once

#include <matrix/matrix/math.hpp>
#include <px4_platform_common/defines.h>

struct sphere_params {
	matrix::Vector3f offset, diag{1.f, 1.f, 1.f}, offdiag;
	float radius{0.2f};
};


/**
 * Least-squares fit of a sphere to a set of points.
 *
 * Fits a sphere to a set of points on the sphere surface.
 *
 * @param x point coordinates on the X axis
 * @param y point coordinates on the Y axis
 * @param z point coordinates on the Z axis
 * @param samples_collected number of points
 * @param max_iterations abort if maximum number of iterations have been reached. If unsure, set to 100.
 * @param params the values to be optimized
 * @param full_ellipsoid whether to just optimize a sphere, or do an ellipsoid optimization
 *
 * NB!! If you optimize the full ellipsoid, you must have already optimized without the full ellipsoid
 *
 * @return 0 on success, 1 on failure
 */
int lm_mag_fit(const float x[], const float y[], const float z[], unsigned int samples_collected, sphere_params &params,
	       bool full_ellipsoid);