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[Susan Stitt]

>
>> We have vector files representing tributaries to a river.
>> Is there a command in GRASS4.0 or 
>> 4.1 that will give me the vector length of either 1) each category
>> in a file or 2) the whole vector file?
>> 
>> Background:  The vector files are dlg stream data which are imported into
>> GRASS4.0.  We can use v.digit to either categorize all the tributaries in 
>> each file  by
>> stream order (in which case we'd like to use choice #1, above)
>> OR we can create files containing only the first order tributaries, 
>> then create a file containing only the 2d order tributaries, etc (in which 
>> case we'd like to use choice #2, above).
>> 
>> Thanks in advance for all help!
>> -Nancy
>>  
>
>There is a wonderful program called v.report, found under src.contrib/SCS/vector
>in GRASS4.1. It reports on length of vectors, areas of polygons, and number of
>sites in GRASS vector layers. Good stuff (reason enough to get 4.1!!) (along
>with v.reclass!).
>
>-- 
>Malcolm D. Williamson - Research Assistant       E-mail: malcolm at cast.uark.edu
>Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
>Ozark Rm. 12                                        Fax: (501) 575-3846 
>University of Arkansas              
>Fayetteville, AR 72701

v.report is the program you need, however be very careful that it is reporting 
the correct information.  We have made several fixes to our code which I will
attempt to attach to this note.  Both our 4.0 and 4.1 versions of this program
did not provide the correct length information until we made some changes to 
the source code....


I have previously sent this to the grassu-list, but am attaching it again:
We did not catch the problem with the
category files, if the dig_cats file is not complete, it won't continue.
However, v.report appears to work with either a complete file, or no
dig_cats file, so my suggestion would be to move the cats file (if incomplete)
to a backup name, run v.report, then move the cats file back, at least until
this bug gets fixed...  

Susan Stitt, National Park Service-GIS Division    susan%nps at cerl.cecer.army.mil



v.report/cmd/do_v_stats.c
	old line 239
		fprintf(dumpfile,"area\n");

	new line 239
		fprintf(dumpfile,"area%d\n",cnt);


v.report/cmd/perimeter.c
	old line 17
		if(i==((np-1)-1))
	new line 17
		if(i==(np-1))


v.report/cmd/prt_report.c
	old line 64
		unit[i].factor    =1.0e+3;
	new line 64
		unit[i].factor    =1.0e-3;


v.report/cmd/stats.c
	old line 39
		sscanf(buf,"%s,%d",atype, &nalloc);
	new line 39
		sscanf(buf,"%s%d",atype, &nalloc);

and

	old line 48
		Gstats = (GSTATS *) G_calloc (nalloc, sizeof(GSTATS));
	new line 48
		Gstats=(GSTATS *) G_malloc ((int)(nalloc * sizeof(GSTATS)));


v.report/cmd/Gmakefile
   old line 23
       $(CC) $(LDFLAGS) -o $@ $(LIST) $(VECTLIB) $(GISLAB) $(LIBES) $(MATHLIB)
   new line 23
       $(CC) $(LDFLAGS) -o $@ $(LIST) $(LIBES) $(VECTLIB) $(GISLIB) $(MATHLIB)


v.report/inter/Gmakefile
   old line 7
       $(CC) $(LDFLAGS) -o $@ $(LIST) $(VECTLIB) $(GISLIB) $(VASK) $(LIBES)
   new line 7
       $(CC) $(LDFLAGS) -o $@ $(LIST) $(GISLIB) $(VASK)