MVT_read_SO_file.m

% MVT_read_SO_file - Create a SO texture file 
%
% Given the name of a formatted texture file from the SO code, return 
% an array of Euler angles and the number of crystals in the file.
% 
% Usage: 
%     [eulers, nxtl] = MVT_read_SO_file(filename)
%
% See also: MVT_read_VPSC_file, MVT_write_SO_file


% Copyright (c) 2013, Andrew Walker
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function [eulers, nxtl] = MVT_read_SO_file(filename)
    % Reads data from a VPSC output or input texture file.
    % Must be Bunge convention and in degrees. Returns eulers, a (3,nxtl) 
    % array of Euler angles (Bunge convention, (1,:) = phi1, (2,:) = Phi
    % and (3,:) = phi2) and a scalar nxtl, specifying the number of 
    % crystals / Euler angle triples.

    % Read data from the file
    fid = fopen(filename); % Read - the default
    fgetl(fid); % F.S.E. axis langhts?? - ignore for now
    L = sscanf(fgetl(fid), '%d %d'); % number of crystals and lines?
    E = fscanf(fid, '%f');
    fclose(fid);
    
    % Get hold of header info
    nxtl = L(1); % Number of crystals
    
    % Build Euler angles array.
    eulers = zeros(3,nxtl);
    eulers(1,:) = E(1:4:4*nxtl);
    eulers(2,:) = E(2:4:4*nxtl);
    eulers(3,:) = E(3:4:4*nxtl);
   
end