Computational routine
eng

##
mat_vps

### File content

    # include "scicos_block4.h"
    # include "../machine.h"
    #include <stdio.h>

    #if WIN32
    #define NULL    0
    #endif

    extern int C2F(dlacpy)();
    extern int C2F(dgeev)();
    extern int C2F(zlaset)();
    extern int C2F(issymmetric)();
    extern int C2F(dsyev)();
    typedef struct
    {         double *LA;
              double *LVR;
              double *dwork;
              double *dwork1;
    } mat_vps_struct ;
    void mat_vps(scicos_block *block,int flag)
    {
     double *u;
     double *y1;
     double *y2;
     int nu;
     int info;
     int i,lwork,lwork1,j,ij,ji;
     int symmetric;
     mat_vps_struct *ptr;

     nu =GetInPortRows(block,1);
     u=GetRealInPortPtrs(block,1);
     y1=GetRealOutPortPtrs(block,1);
     y2=GetImagOutPortPtrs(block,1);
     lwork1=3*nu;
     lwork=3*nu-1;
                 /*init : initialization*/
    if (flag==4)
       {if((*(block->work)=(mat_vps_struct*) scicos_malloc(sizeof(mat_vps_struct)))==NULL)
    	{set_block_error(-16);
    	 return;}
        ptr=*(block->work);
        if((ptr->LA=(double*) scicos_malloc(sizeof(double)*(nu*nu)))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->LVR=(double*) scicos_malloc(sizeof(double)*(nu*nu)))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->LA);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->dwork=(double*) scicos_malloc(sizeof(double)*lwork))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->LVR);
    	 scicos_free(ptr->LA);
    	 scicos_free(ptr);
    	 return;}
        if((ptr->dwork1=(double*) scicos_malloc(sizeof(double)*lwork1))==NULL)
    	{set_block_error(-16);
    	 scicos_free(ptr->dwork);
    	 scicos_free(ptr->LVR);
    	 scicos_free(ptr->LA);
    	 scicos_free(ptr);
    	 return;}
       }

           /* Terminaison */
    else if (flag==5)
       {ptr=*(block->work);
        if((ptr->dwork1)!=NULL){
        	scicos_free(ptr->LA);
        	scicos_free(ptr->LVR);
        	scicos_free(ptr->dwork);
        	scicos_free(ptr->dwork1);
        	scicos_free(ptr);
        	return;}
       }

    else
       {
        ptr=*(block->work);
        C2F(dlacpy)("F",&nu,&nu,u,&nu,ptr->LA,&nu);
       symmetric=1;
        for (j=0;j<nu;j++)
    	{for (i=j;i<nu;i++)
    		{ij=i+j*nu;
    		 ji=j+i*nu;
    		if (i!=j)
    			{if (*(ptr->LA+ij)==*(ptr->LA+ji)) symmetric*= 1;
    			 else { symmetric*=0;break;}}}}
        if (symmetric==1)
    	{C2F(dsyev)("N","U",&nu,ptr->LA,&nu,y1,ptr->dwork,&lwork,&info);
    	 if (info!=0)
    	    	{if (flag!=6)
    		{set_block_error(-7);
    		return;
    		}}
    	}
       else
    	{C2F(dgeev)("N","N",&nu,ptr->LA,&nu,y1,y2,ptr->dwork1,&nu,ptr->LVR,&nu,ptr->dwork1,&lwork1,&info);
            if (info!=0)
    	    	{if (flag!=6)
    		{set_block_error(-7);
    		return;
    		}}
    	}
       }
    }