MVT_rot_from_Euler.m

% MVT_rot_from_Euler - Convert Euler angles to rotation matrix 
%
% Given three Euler angles phi1, Phi, phi2 (Bunge notation, in degrees)
% return a rotation matrix, g, representing the rotation.
% 
% Usage: 
%     [g] = MVT_rot_to_Euler(phi1, Phi, phi2)
%
% Notes: This is the 'passive' rotation, take the transpose for the 
%     active case.
%
% See also: MS_rotEuler MVT_rot_to_Euler


% Copyright (c) 2012, Andrew Walker
% All rights reserved.
% 
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% with or without modification, are permitted provided 
% that the following conditions are met:
% 
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%      and the following disclaimer.
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%    * Neither the name of the University of Bristol nor the names 
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% 
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function [ g ] = MVT_rot_from_Euler(phi1, theta, phi2)
    % Given three Euler angles phi1, Phi, phi2 (Bunge notation, 
    % in degrees) return a rotation matrix, g, representing the 
    % rotation. This is the 'passive' rotation.
    
    % Pre-compute trig functions.
    cp1 = cos(phi1*pi/180.0);
    sp1 = sin(phi1*pi/180.0);
    cp2 = cos(phi2*pi/180.0);
    sp2 = sin(phi2*pi/180.0);
    cth = cos(theta*pi/180.0);
    sth = sin(theta*pi/180.0);

    % Form rotation matrix for Bunge convention of 
    % Euler angles, see eq 24 (pg81) of "Preferred
    % orientation in deformed meals and rocks... H-K Wenk (ed)"
    g = [cp1*cp2 - sp1*sp2*cth, sp1*cp2 + cp1*sp2*cth, sp2*sth ; ...
        -1*cp1*sp2 - sp1*cp2*cth, -1*sp1*sp2 + cp1*cp2*cth, cp2*sth; ...
        sp1*sth, -1*cp1*sth, cth];
    
   
end