static int pack_double(grib_accessor* a, const double* val, size_t *len) {

    grib_accessor_data_complex_packing* self =  (grib_accessor_data_complex_packing*)a;

    size_t i = 0;
    int ret = GRIB_SUCCESS;
    long   hcount = 0;
    long   lcount = 0;
    long   hpos = 0;
    long   lup = 0;
    long   mmax = 0;
    long   n_vals = 0;
    double *scals  = NULL;

    double s = 0;
    double d = 0;

    unsigned char* buf    = NULL;

    size_t         buflen = 0;
    size_t         hsize = 0;
    size_t         lsize = 0;

    unsigned char* hres = NULL;
    unsigned char* lres = NULL;

    long   lpos = 0;
    long   maxv = 0;

    long   offsetdata           = 0;
    long   bits_per_value          = 0;
    double reference_value      = 0;
    long   binary_scale_factor         = 0;
    long   decimal_scale_factor = 0;
    long   laplacianOperatorIsSet = 0;

    double laplacianOperator = 0;
    long   sub_j= 0;
    long   sub_k= 0;
    long   sub_m= 0;
    long   pen_j= 0;
    long   pen_k= 0;
    long   pen_m= 0;
    long   GRIBEX_sh_bug_present =0;
    long   ieee_floats =0;
    double min = 0;
    double max = 0;
    double current_val = 0;
    short mixmax_unset = 0;
    int bytes;

    encode_float_proc encode_float = NULL;

    if (*len ==0) return GRIB_NO_VALUES;

    if((ret = grib_get_long_internal(a->parent->h,self->offsetdata,&offsetdata)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->bits_per_value,&bits_per_value)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_long_internal(a->parent->h,self->decimal_scale_factor,&decimal_scale_factor)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_long_internal(a->parent->h,self->GRIBEX_sh_bug_present,&GRIBEX_sh_bug_present)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_long_internal(a->parent->h,self->ieee_floats,&ieee_floats)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_long_internal(a->parent->h,self->laplacianOperatorIsSet,&laplacianOperatorIsSet)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_double_internal(a->parent->h,self->laplacianOperator,&laplacianOperator)) != GRIB_SUCCESS)
        return ret;

    if((ret = grib_get_long_internal(a->parent->h,self->sub_j,&sub_j)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->sub_k,&sub_k)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->sub_m,&sub_m)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->pen_j,&pen_j)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->pen_k,&pen_k)) != GRIB_SUCCESS)
        return ret;
    if((ret = grib_get_long_internal(a->parent->h,self->pen_m,&pen_m)) != GRIB_SUCCESS)
        return ret;

    self->dirty=1;


    switch (ieee_floats) {
    case 0:
        encode_float =grib_ibm_to_long;
        bytes=4;
        break;
    case 1:
        encode_float =grib_ieee_to_long;
        bytes=4;
        break;
    case 2:
        encode_float =grib_ieee64_to_long;
        bytes=8;
        break;
    default:
        return GRIB_NOT_IMPLEMENTED;
    }

    Assert (sub_j == sub_k); Assert( sub_j == sub_m);
    Assert (pen_j == pen_k); Assert( pen_j == pen_m);

    n_vals = (pen_j+1)*(pen_j+2);
    d = grib_power(decimal_scale_factor,10) ;

    if(*len != n_vals){
        grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,"COMPLEX_PACKING : wrong number of values, expected %d - got %d",n_vals,*len);
        return GRIB_INTERNAL_ERROR;
    }

    if (pen_j == sub_j) {
        double* values;
        if (d) {
            values=(double*)grib_context_malloc_clear(a->parent->h->context,sizeof(double)*n_vals);
            for (i=0;i<n_vals;i++) values[i]=val[i]*d;
        } else {
            values=(double*)val;
        }
        buflen=n_vals*bytes;
        buf = (unsigned char*)grib_context_malloc_clear(a->parent->h->context,buflen);
        grib_ieee_encode_array(a->parent->h->context,values,n_vals,bytes,buf);
        if (d) grib_context_free(a->parent->h->context,values);
        grib_buffer_replace(a, buf, buflen,1,1);
        grib_context_free(a->parent->h->context,buf);
        return 0;
    }

    if(!laplacianOperatorIsSet) {
        laplacianOperator = calculate_pfactor(a->parent->h->context,val,pen_j,sub_j);
        if((ret = grib_set_double_internal(a->parent->h,self->laplacianOperator,laplacianOperator))
                != GRIB_SUCCESS) return ret;
        grib_get_double_internal(a->parent->h,self->laplacianOperator,&laplacianOperator);
    }

    /*
     printf("PACKING LAPLACE set=%ld value=%.20f\n",laplacianOperatorIsSet,laplacianOperator);
    */

    hsize = 4*(sub_k+1)*(sub_k+2);
    lsize = ((n_vals - ((sub_k+1)*(sub_k+2)))*bits_per_value)/8;

    buflen = hsize+lsize;

    buf  = (unsigned char*)grib_context_malloc(a->parent->h->context,buflen);
    hres = buf;
    lres = buf+hsize;

    maxv = pen_j+1;

    lpos = 0;
    hpos = 0;

    scals   = (double*) grib_context_malloc(a->parent->h->context,maxv*sizeof(double));
    Assert(scals);

    scals[0] =0;
    for(i=1;i<maxv;i++)
        scals[i] = ((double)pow(i*(i+1),laplacianOperator));


    i=0;

    mmax = 0;
    maxv = pen_j+1;
    i=0;
    lcount=0;
    hcount=0;
    sub_k = sub_j;

    while(maxv>0)
    {
        lup=mmax;

        if(sub_k>=0)
        {
            i   += 2*(sub_k+1);
            lup +=    sub_k+1 ;
            hcount += sub_k+1 ;
            sub_k--;
        }

        for(lcount=hcount; lcount < maxv ; lcount++)
        {
            current_val = ((val[i++]*d) * scals[lup]);
            if(mixmax_unset == 0){
                max = current_val;
                min = current_val;
                mixmax_unset = 1;
            }

            if(current_val > max) max = current_val;
            if(current_val < min) min = current_val;

            current_val = ((val[i++]*d) * scals[lup]);
            if(current_val > max) max = current_val;
            if(current_val < min) min = current_val;

            lup++;
        }
        maxv--;
        hcount=0;
        mmax++;
    }

    if (grib_get_nearest_smaller_value(a->parent->h,self->reference_value,min,&reference_value)
            !=GRIB_SUCCESS) {
        grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                "unable to find nearest_smaller_value of %g for %s",min,self->reference_value);
        exit(GRIB_INTERNAL_ERROR);
    }
    binary_scale_factor = grib_get_binary_scale_fact(max,reference_value,bits_per_value,&ret);

    if (ret==GRIB_UNDERFLOW) {
        d=0;
        binary_scale_factor = 0;
        reference_value=0;

    }
    s = grib_power(-binary_scale_factor,2);

    /* printf("D : %.30f\n",d); */

    i=0;

    mmax = 0;
    maxv = pen_j+1;
    i=0;
    lcount=0;
    hcount=0;
    sub_k = sub_j;

    while(maxv>0)
    {
        lup=mmax;

        if(sub_k>=0)
        {
            for(hcount=0;hcount<sub_k+1;hcount++)
            {
                if ( GRIBEX_sh_bug_present && hcount==sub_k ) {
                    /* _test(val[i]*d*scals[lup],1); */
                    grib_encode_unsigned_long(hres, encode_float((val[i++]*d)*scals[lup]) , &hpos, 32);
                    /* _test(val[i]*d*scals[lup],1); */
                    grib_encode_unsigned_long(hres, encode_float((val[i++]*d)*scals[lup]) , &hpos, 32);
                }else{

                    /* _test(val[i]*d,0); */

                    grib_encode_unsigned_long(hres, encode_float(val[i++]*d) , &hpos, 32);
                    /* _test(val[i]*d,0); */
                    grib_encode_unsigned_long(hres, encode_float(val[i++]*d) , &hpos, 32);
                }
                lup++;
            }
            sub_k--;
        }

#if FAST_BIG_ENDIAN
        grib_encode_double_array_complex((maxv-hcount)*2,&(val[i]),bits_per_value,reference_value,&(scals[lup]),d,s,lres,&lpos);
        i+=(maxv-hcount)*2;
#else
        if (bits_per_value % 8) {
            for(lcount=hcount; lcount < maxv ; lcount++)
            {
                current_val = (((((val[i++]*d) * scals[lup])-reference_value)*s)+0.5);
                if(current_val < 0)
                    grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                            "COMPLEX_PACKING : negative coput before packing (%g)", current_val);
                grib_encode_unsigned_longb(lres, current_val, &lpos, bits_per_value);

                current_val = (((((val[i++]*d) * scals[lup])-reference_value)*s)+0.5);
                if(current_val < 0)
                    grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                            "COMPLEX_PACKING : negative coput before packing (%g)", current_val);
                grib_encode_unsigned_longb(lres, current_val, &lpos, bits_per_value);
                lup++;
            }
        } else {
            for(lcount=hcount; lcount < maxv ; lcount++)
            {
                current_val = (((((val[i++]*d) * scals[lup])-reference_value)*s)+0.5);
                if(current_val < 0)
                    grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                            "COMPLEX_PACKING : negative coput before packing (%g)", current_val);
                grib_encode_unsigned_long(lres, current_val, &lpos, bits_per_value);

                current_val = (((((val[i++]*d) * scals[lup])-reference_value)*s)+0.5);
                if(current_val < 0)
                    grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                            "COMPLEX_PACKING : negative coput before packing (%g)", current_val);
                grib_encode_unsigned_long(lres, current_val, &lpos, bits_per_value);
                lup++;
            }
        }
#endif

        maxv--;
        hcount=0;
        mmax++;
    }

    if(((hpos/8) != hsize) &&((lpos/8) != lsize))
    {
        grib_context_log(a->parent->h->context,GRIB_LOG_ERROR,
                "COMPLEX_PACKING : Mismatch in packing between high resolution and low resolution part");
        grib_context_free(a->parent->h->context,buf);
        grib_context_free(a->parent->h->context,scals);
        return GRIB_INTERNAL_ERROR;
    }

    buflen = ((hpos + lpos)/8);

    if((ret = grib_set_double_internal(a->parent->h,self->reference_value, reference_value)) != GRIB_SUCCESS)
        return ret;
    {
        /* Make sure we can decode it again */
        double ref = 1e-100;
        grib_get_double_internal(a->parent->h,self->reference_value,&ref);
        Assert(ref == reference_value);
    }

    if((ret = grib_set_long_internal(a->parent->h,self->binary_scale_factor, binary_scale_factor)) != GRIB_SUCCESS)
        return ret;

    grib_buffer_replace(a, buf, buflen,1,1);
    grib_context_free(a->parent->h->context,buf);
    grib_context_free(a->parent->h->context,scals);

    return ret;

}
static int pack_double(grib_accessor* a, const double* val, size_t *len)
{
    grib_accessor_data_2order_packing* self =  (grib_accessor_data_2order_packing*)a;
    grib_handle* gh = grib_handle_of_accessor(a);

    size_t i = 0;
    size_t j = 0;
    size_t n_vals = *len;
    size_t buff_len = 0;
    double divisor = 1;
    long     vcount = 0;
    int      err = 0;
    long     bias = 0;
    double   reference_value;
    long     binary_scale_factor;
    long     bits_per_value;
    /*long     bit_per_val_rectified_for_gribex;*/
    long     decimal_scale_factor;
    long     n1 = 0;
    long     n2 = 0;
    long     p1 = 0;
    long    n_unused_bits = 0;
    long   used_bits = 0;
    long   offsetsection  = 0;
    long   snd_bitmap     = 0;
    long   snd_ordr_wdiff = 0;

    long   matrix_values  = 0;

    long   general_ext       = 0;
    long   boustrophedonic   = 0;
    long   two_ordr_spd      = 0;
    long   plus1_spd         = 0;

    long   octet_start_group = 0;
    long   width_spd_sp_desc = 0;

    unsigned char* buf        = NULL;
    unsigned char* buf_size_of_groups   = NULL;
    unsigned char* buf_width_of_group = NULL;
    unsigned char* buf_refs   = NULL;
    unsigned char* buf_vals   = NULL;

    double d = 0;

    unsigned long*  sec_val    = NULL;
    unsigned long*  group_val  = NULL;

    short  n_sp_diff = 0;
    unsigned char* bitmap=NULL;
    grib_accessor* abitmap=NULL;
    size_t bitmap_len=0;

#if KEEP_OLD == 1

#else
    second_order_packed* sd = NULL;
#endif

    long   bitp = 0;
    long   pointer_of_group_size = 0;
    long   pointer_of_group_width = 0;
    long   refsp = 0;
    long   nap = 0;
    long offsetdata = 0;

    double max;
    double min;
    int extraValues=0;

    size_t nv =0;

    if (*len ==0) return GRIB_NO_VALUES;

    if((err = grib_get_long_internal(gh,self->offsetsection,&offsetsection)) != GRIB_SUCCESS) return err;
    if((err = grib_get_long_internal(gh,self->offsetdata,&offsetdata)) != GRIB_SUCCESS)
        return err;
    if((err = grib_get_long_internal(gh,self->bits_per_value,&bits_per_value)) != GRIB_SUCCESS) return err;
    if((err = grib_get_long_internal(gh,self->decimal_scale_factor, &decimal_scale_factor))  != GRIB_SUCCESS)  return err;
    if((err = grib_get_long_internal(gh,self->matrix_values, &matrix_values)) != GRIB_SUCCESS)return err;
    if((err = grib_get_long_internal(gh,self->snd_bitmap, &snd_bitmap)) != GRIB_SUCCESS)  return err;
    if((err = grib_get_long_internal(gh,self->snd_ordr_wdiff, &snd_ordr_wdiff)) != GRIB_SUCCESS) return err;
    if((err = grib_get_long_internal(gh,self->general_ext, &general_ext)) != GRIB_SUCCESS)  return err;
    if((err = grib_get_long_internal(gh,self->boustrophedonic, &boustrophedonic)) != GRIB_SUCCESS)  return err;
    if((err = grib_get_long_internal(gh,self->width_spd_sp_desc, &width_spd_sp_desc)) != GRIB_SUCCESS) return err;
    if((err = grib_get_long_internal(gh,self->nap, &nap)) != GRIB_SUCCESS) return err;

    if ((abitmap=grib_find_accessor(gh,self->bitmap))!=NULL) {
        bitmap_len=grib_byte_count(abitmap);
        bitmap=(unsigned char*)grib_context_malloc_clear(a->context,sizeof(char)*bitmap_len);
        err=grib_unpack_bytes(abitmap,bitmap,&bitmap_len);
        if (err) {grib_context_free(a->context,bitmap); return err;}
    }

    two_ordr_spd = 1;
    plus1_spd = 0;

    if(bits_per_value == 0)
        return GRIB_NOT_IMPLEMENTED;

    n_sp_diff = two_ordr_spd*2+plus1_spd;
    /*     calculation of integer array   */

    sec_val  = (unsigned long*)grib_context_malloc(a->context,(n_vals)*sizeof(long));
    d = grib_power(decimal_scale_factor,10) ;
    max = val[0];
    min = max;
    for(i=0;i< n_vals;i++)
    {
        if      ( val[i] > max ) max = val[i];
        else if ( val[i] < min ) min = val[i];
    }
    min *= d;
    max *= d;

    /*bit_per_val_rectified_for_gribex = bits_per_value+8-bits_per_value%8;*/
    if (grib_get_nearest_smaller_value(gh,self->reference_value,min,&reference_value)
            !=GRIB_SUCCESS) {
        grib_context_log(a->context,GRIB_LOG_ERROR,
                "unable to find nearest_smaller_value of %g for %s",min,self->reference_value);
        return GRIB_INTERNAL_ERROR;
    }

    /*  the scale factor in Grib 1 is adjusted in gribex, for "normalization purpose" ... ?*/
    binary_scale_factor    = grib_get_binary_scale_fact(max,reference_value,bits_per_value,&err);

    divisor         = grib_power(-binary_scale_factor,2);


    for(i=0;i< n_vals;i++)
        sec_val[i] = (unsigned long)((((val[i]*d)-reference_value)*divisor)+0.5);

    /*  reverse the rows*/
    if(boustrophedonic)
        reverse_rows(sec_val,n_vals,nap,bitmap,bitmap_len);


    if(snd_ordr_wdiff)
        if((err =  spatial_difference(a->context,sec_val, n_vals, n_sp_diff, &bias))){
            grib_context_free(a->context,sec_val);
            return err;
        }



    /*   for(i=0;i < 10;i++)
      printf("packing value [%d] %g %ld     %ld bias %ld <<\n", i, val[i],sec_val[i],binary_scale_factor,bias );
     */
    nv        = n_vals-n_sp_diff;
    group_val = sec_val+n_sp_diff;

#if KEEP_OLD == 1

#else
    sd = grib_get_second_order_groups(a->context, group_val, nv);
#endif

    bitp   = 0;
    p1     = sd->size_of_group_array;

    bitp                         =   (width_spd_sp_desc*(n_sp_diff+1)) ;
    octet_start_group            =   (bitp+7)/8;

    bitp                         =   (p1*sd->nbits_per_widths);
    octet_start_group           +=   (bitp+7)/8;

    bitp                         =   (octet_start_group*8) + (sd->nbits_per_group_size*p1);
    n1                           =   (bitp+7)/8;

    bitp                         =   n1*8 + bits_per_value*p1;
    n2                           =   (bitp+7)/8;

    used_bits = n2*8;

    buff_len     = (n2+sd->packed_byte_count);

    if((a->offset+buff_len)%2) buff_len++;

    buf = NULL;
    buf = (unsigned char*)grib_context_malloc_clear(a->context,buff_len);

    buf_width_of_group    =  buf;
    buf_size_of_groups    =  buf+octet_start_group;
    buf_refs    =  buf+n1;
    buf_vals    =  buf+n2;

    pointer_of_group_size    = 0;
    pointer_of_group_width   = 0;
    refsp  = 0;
    bitp   = 0;

    for(i=0;i < n_sp_diff;i++)
        grib_encode_unsigned_longb(buf_width_of_group,sec_val[i],  &pointer_of_group_width,  width_spd_sp_desc);

    grib_encode_signed_longb(buf_width_of_group, bias, &pointer_of_group_width,  width_spd_sp_desc);

    if(pointer_of_group_width%8)
        pointer_of_group_width = 8+(pointer_of_group_width-(pointer_of_group_width%8));

    vcount    = n_sp_diff;

    for(i = 0;i<p1;i++){
        grib_encode_unsigned_longb(buf_width_of_group,sd->array_of_group_width[i],&pointer_of_group_width,sd->nbits_per_widths);
        grib_encode_unsigned_longb(buf_size_of_groups,sd->array_of_group_size[i], &pointer_of_group_size ,sd->nbits_per_group_size);
        grib_encode_unsigned_longb(buf_refs,  sd->array_of_group_refs[i],  &refsp  , bits_per_value);
        used_bits += sd->array_of_group_size[i]*sd->array_of_group_width[i];
        for(j=0; j < sd->array_of_group_size[i];j++){
            grib_encode_unsigned_longb(buf_vals, sec_val[vcount+j]-sd->array_of_group_refs[i] ,&bitp , sd->array_of_group_width[i]);

            /*    if(vcount+j < 10)
             printf(">>packing value [%ld] %g %ld     %ld nb %ld <<\n", vcount+j, val[vcount+j],sec_val[vcount+j],binary_scale_factor,sd->array_of_group_refs[i] );*/
        }
        vcount+= sd->array_of_group_size[i];
    }
    n_unused_bits = (buff_len*8)-used_bits;

    grib_buffer_replace(a, buf,buff_len,1,1);

    if((buff_len + (offsetdata-offsetsection)) %2) {
        buff_len ++;
        grib_update_size(a,buff_len);
    }

    octet_start_group += 1+ a->offset-offsetsection;
    if((err = grib_set_long_internal(gh,self->octet_start_group, octet_start_group)) != GRIB_SUCCESS) return err;

    n1 += 1+a->offset-offsetsection;
    if((err = grib_set_long_internal(gh,self->n1,n1)) != GRIB_SUCCESS) return err;

    n2 += 1+a->offset-offsetsection;
    if((err = grib_set_long_internal(gh,self->n2,n2)) != GRIB_SUCCESS) return err;

    extraValues=0;
    while (p1 > 65535) {
        p1-=65536;
        extraValues++;
    }

    if((err = grib_set_long_internal(gh,self->p1,p1)) != GRIB_SUCCESS) return err;

    if((err = grib_set_long_internal(gh,self->extraValues,extraValues)) != GRIB_SUCCESS) return err;

    if((err = grib_set_long_internal(gh,self->p2,n_vals - n_sp_diff)) != GRIB_SUCCESS) return err;

    if((err = grib_set_double_internal(gh,self->reference_value,    reference_value)) != GRIB_SUCCESS)return err;

    {
        /* Make sure we can decode it again */
        double ref = 1e-100;
        grib_get_double_internal(gh,self->reference_value,&ref);
        Assert(ref == reference_value);
    }

    if((err = grib_set_long_internal(gh,self->binary_scale_factor,         binary_scale_factor)) != GRIB_SUCCESS)  return err;

    if((err = grib_set_long_internal(gh,self->decimal_scale_factor, decimal_scale_factor))  != GRIB_SUCCESS)  return err;
    if((err = grib_set_long_internal(gh,self->width_widths,  sd->nbits_per_widths)) != GRIB_SUCCESS) return err;
    if((err = grib_set_long_internal(gh,self->width_lengths, sd->nbits_per_group_size)) != GRIB_SUCCESS) return err;


    err = grib_set_long_internal(gh,self->half_byte, n_unused_bits);
    if(err != GRIB_SUCCESS) return err;

#if KEEP_OLD == 1

#else

    grib_free_second_order_groups(a->context,sd);
#endif
    ;

    grib_context_free(a->context,buf);
    grib_context_free(a->context,sec_val);
    if (bitmap!=NULL) grib_context_free(a->context,bitmap);

    return GRIB_SUCCESS;
}