Cartesian2Spherical.m

%{
 * Copyright (C) 2013-2025, The Regents of The University of Michigan.
 * All rights reserved.
 * This software was developed in the Biped Lab (https://www.biped.solutions/) 
 * under the direction of Jessy Grizzle, grizzle@umich.edu. This software may 
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 * AUTHOR: Bruce JK Huang (bjhuang[at]umich.edu)
 * WEBSITE: https://www.brucerobot.com/
 %}


function spherical_data = Cartesian2Spherical(data)
    if(isempty(data))
        warning("empty input into the Cartesian2Spherical function");
    end
    spherical_data = data;
    %D = x^2 + y^2 + z^2;
    %elevation_angle = arccos(z/D)
    %azimuth_angle = arctan(y/x)
    spherical_data(1,:) = sqrt(data(1,:).^2 + data(2,:).^2 + data(3,:).^2);
    spherical_data(2,:) = acos(data(3,:)./spherical_data(1,:));
    spherical_data(3,:) = atan2(data(2,:), data(1,:));
end