function [cindx,direct,multipl] = lagrangeindicies
  
% address fields for addressing the elements of the  Lagrangian elasticity tensor
% cindx is a 3x3x3x3 field that contains numbers between 1 and 21 to 
% to point at the representative element.
% direct is a 21x4 array that is used to address a fourth order tensor
% with the symmetry conditions of the
% multipl contains for each of these fields how often they occure due 
% to symmetries.

  cindx = zeros(3,3,3,3);
  multipl = zeros(21,1);
  direct = zeros(21,4);
  kk=0;
  for i=1:3,
    for j=1:3,
      for k=1:3,
	for l=1:3,
	  if (cindx(i,j,k,l)==0),
	    kk=kk+1;
	    cindx(i,j,k,l)=kk;  multipl(kk)=multipl(kk)+1; 
	    direct(kk,:) = [i,j,k,l];
	    if cindx(i,j,l,k) ==0, cindx(i,j,l,k)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(j,i,k,l) ==0, cindx(j,i,k,l)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(j,i,l,k) ==0, cindx(j,i,l,k)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(k,l,i,j) ==0, cindx(k,l,i,j)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(k,l,j,i) ==0, cindx(k,l,j,i)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(l,k,i,j) ==0, cindx(l,k,i,j)=kk; multipl(kk)=multipl(kk)+1; end;
	    if cindx(l,k,j,i) ==0, cindx(l,k,j,i)=kk; multipl(kk)=multipl(kk)+1; end;
	  end;
	end;
      end;
    end;
  end;