AssembleSparse.m

function [Ksr,Ksc,Ksv,Fsr,Fsv,fc,kc] = AssembleSparse(iele,nnpe,np,ke,fe,Ksr,Ksc,Ksv,Fsr,Fsv,fc,kc)
% assembles elemental force and stiffness matrices into global counterparts
% assuming sparse matrices

    for  i=1:nnpe
        
      i3 = 3*np(iele,i);
      i2 = i3-1;
      i1 = i3-2;
      ii3 = 3*i;
      ii2 = ii3-1;
      ii1 = ii3-2;       
  
        Fsr(fc)=i1; 
        Fsv(fc)=fe(ii1); 
        fc=fc+1;
        
        Fsr(fc)=i2; 
        Fsv(fc)=fe(ii2);   
        fc=fc+1;
        
        Fsr(fc)=i3; 
        Fsv(fc)=fe(ii3); 
        fc=fc+1;
        
        for j=1:nnpe
            
            j3=3*np(iele,j);	
            j2=j3-1;
            j1=j3-2;
            jj3= 3*j;
            jj2= jj3-1;
            jj1= jj3-2;
            
            Ksr(kc)=i1; 
            Ksc(kc)=j1; 
            Ksv(kc)=ke(ii1,jj1); 
            kc=kc+1;
            
            Ksr(kc)=i1; 
            Ksc(kc)=j2; 
            Ksv(kc)=ke(ii1,jj2); 
            kc=kc+1;
                        
            Ksr(kc)=i1; 
            Ksc(kc)=j3; 
            Ksv(kc)=ke(ii1,jj3); 
            kc=kc+1;
            
            Ksr(kc)=i2; 
            Ksc(kc)=j1; 
            Ksv(kc)=ke(ii2,jj1); 
            kc=kc+1;
            
            Ksr(kc)=i2; 
            Ksc(kc)=j2; 
            Ksv(kc)=ke(ii2,jj2); 
            kc=kc+1;
                        
            Ksr(kc)=i2; 
            Ksc(kc)=j3; 
            Ksv(kc)=ke(ii2,jj3); 
            kc=kc+1;
            
            Ksr(kc)=i3; 
            Ksc(kc)=j1; 
            Ksv(kc)=ke(ii3,jj1); 
            kc=kc+1;
            
            Ksr(kc)=i3; 
            Ksc(kc)=j2; 
            Ksv(kc)=ke(ii3,jj2); 
            kc=kc+1;
                        
            Ksr(kc)=i3; 
            Ksc(kc)=j3; 
            Ksv(kc)=ke(ii3,jj3); 
            kc=kc+1;
            
            
        end
    end