[GRASS-dev] d.vect -a shows only some elements

[Moritz Lennert]

Martin Landa wrote:
> Hi,
> 
> 2006/10/21, Moritz Lennert <mlennert at club.worldonline.be>:
> 
> [snip]
> 
>> > you are right (if I understand well), adding
>> >
>> > db_CatValArray_sort (&cvarr_rgb);
>> >
>> > should solve the problem. I wonder why db_select_CatValArray sorts
>> > cvarr->value by category number only for data type int or double...
>> > (?), see
>> >
>> > 00300     if ( type == DB_C_TYPE_INT )
>> > 00301         qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal),
>> > cmpcat);
>> > 00302     else if ( type == DB_C_TYPE_DOUBLE )
>> > 00303         qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal),
>> > cmpcat);
>> >
>>
>> Applying below patch directly to db_select_CatValArray solves the problem
>> for me, but I don't know if this might cause other problems, even 
>> though I
>> doubt it.
>>
>> Any ideas ?
>>
>> Moritz
>>
>> Index: lib/db/dbmi_client/select.c
>> ===================================================================
>> RCS file: /grassrepository/grass6/lib/db/dbmi_client/select.c,v
>> retrieving revision 1.8
>> diff -u -r1.8 select.c
>> --- lib/db/dbmi_client/select.c 14 Jul 2006 16:41:22 -0000      1.8
>> +++ lib/db/dbmi_client/select.c 20 Oct 2006 23:22:26 -0000
>> @@ -297,10 +297,7 @@
>>      db_close_cursor(&cursor);
>>      db_free_string ( &stmt );
>>
>> -    if ( type == DB_C_TYPE_INT )
>> -        qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal), cmpcat);
>> -    else if ( type == DB_C_TYPE_DOUBLE )
>> -        qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal), cmpcat);
>> +    db_CatValArray_sort ( cvarr );
>>
>>      return (nrows);
>>  }
> 
> in this case the array is sorted twice for datatype DB_C_TYPE_INT and
> DB_C_TYPE_DOUBLE, I suggest
> 
> Index: lib/db/dbmi_client/select.c
> ===================================================================
> RCS file: /home/grass/grassrepository/grass6/lib/db/dbmi_client/select.c,v
> retrieving revision 1.8
> diff -u -r1.8 select.c
> --- lib/db/dbmi_client/select.c    14 Jul 2006 16:41:22 -0000    1.8
> +++ lib/db/dbmi_client/select.c    21 Oct 2006 07:43:35 -0000
> @@ -297,9 +297,8 @@
>     db_close_cursor(&cursor);
>     db_free_string ( &stmt );
> 
> -    if ( type == DB_C_TYPE_INT )
> -        qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal), cmpcat);
> -    else if ( type == DB_C_TYPE_DOUBLE )
> +    if ( type == DB_C_TYPE_INT || type == DB_C_TYPE_DOUBLE ||
> +     type == DB_C_TYPE_STRING )
>         qsort( (void *) cvarr->value, nrows, sizeof(dbCatVal), cmpcat);
> 
>     return (nrows);
> 
> Not sure if you need to check "type" here (what about DB_C_TYPE_DATETIME)??


Don't know, either. The whole idea is to have the array sorted by cat
when it is returned. No reason that this should be any different
whatever the datatype of the attached data column.

This is why I suggested replacing the whole thing by one simple call to

db_CatValArray_sort ( cvarr );

where db_CatValArray_sort simply contains:

  qsort( (void *) arr->value, arr->n_values, sizeof(dbCatVal), cmpcat);

i.e. exactly the same sorting call.

So, why would that sort the array twice ?


Moritz