Computational routine
eng

##
mat_lu

### File content

    # include "scicos_block4.h"
    # include "../machine.h"
    #include <stdio.h>
    extern int C2F(dgetrf)();
    extern int C2F(dlaswp)();

    #if WIN32
    #define NULL    0
    #endif

    #ifndef min
    #define min(a,b) ((a) <= (b) ? (a) : (b))
    #endif

    #ifndef max
    #define max(a,b) ((a) >= (b) ? (a) : (b))
    #endif

    typedef struct
    {         int *ipiv;
              double *dwork;
    	  double *IL;
    	  double *IU;
    } mat_lu_struct ;
    void mat_lu(scicos_block *block,int flag)
    {
     double *u;
     double *y1;
     double *y2;
     int mu;
     int nu;
     int info;
     int i,j,l,ij,ik;
     mat_lu_struct *ptr;

     mu =GetInPortRows(block,1);
     nu =GetInPortCols(block,1);
     u=GetRealInPortPtrs(block,1);
     y1=GetRealOutPortPtrs(block,1);
     y2=GetRealOutPortPtrs(block,2);
     l=min(mu,nu);
                 /*init : initialization*/
    if (flag==4)
       {if((*(block->work)=(mat_lu_struct*) scicos_malloc(sizeof(mat_lu_struct)))==NULL)
    	{set_block_error(-16);
    	 return;}
        ptr=*(block->work);
        if((ptr->ipiv=(int*) scicos_malloc(sizeof(int)*nu))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->dwork=(double*) scicos_malloc(sizeof(double)*(mu*nu)))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->ipiv);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->IL=(double*) scicos_malloc(sizeof(double)*(mu*l)))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->dwork);
    	 scicos_free(ptr->ipiv);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->IU=(double*) scicos_malloc(sizeof(double)*(l*nu)))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->IL);
    	 scicos_free(ptr->dwork);
    	 scicos_free(ptr->ipiv);
    	 scicos_free(ptr);
    	 return;}
       }

           /* Terminaison */
    else if (flag==5)
       {ptr=*(block->work);
        if((ptr->IU)!=NULL){
        	scicos_free(ptr->ipiv);
        	scicos_free(ptr->dwork);
        	scicos_free(ptr->IL);
        	scicos_free(ptr->IU);
        	scicos_free(ptr);
        	return;}
       }

    else
       {
        ptr=*(block->work);
        for (i=0;i<(mu*nu);i++)   { ptr->dwork[i]=u[i];}
        C2F(dgetrf)(&mu,&nu,ptr->dwork,&mu,ptr->ipiv,&info);
        if (info !=0)
           {if (flag!=6)
       	{set_block_error(-7);
            return;}}
       for (j=0;j<l;j++)
    	{for (i=0;i<mu;i++)
    	     {ij=i+j*mu;
    	      if (i==j)
    		{*(y2+ij)=1;}
    	      else if (i>j)
    		{*(y2+ij)=*(ptr->dwork+ij);}
    	      else
    		{*(y2+ij)=0;}
    	      }
    	}
    	for (j=0;j<nu;j++)
    	{for (i=0;i<l;i++)
    	     {ij=i+j*l;
    	      ik=i+j*mu;
    	      if (i<=j)
    		{*(y1+ij)=*(ptr->dwork+ik);}
    	      else
    		{*(y1+ij)=0;}
    	      }
     	}
       }
    }