[GRASS-dev] r.univar: allow multiple rasters to be processed

[Ivan Shmakov]

>>>>> Hamish  <hamish_b at yahoo.com> writes:

 >> Is there some fundamental reason why r.univar has separate cases for
 >> CELL/FCELL/DCELL types, rather than just working in DCELL
 >> throughout?

 > I can't remember with any certainty why I did it that way; it's been
 > like that since the first CVS checkin.

	Please consider the following patch.

diff --git a/raster/r.univar2/r.univar_main.c b/raster/r.univar2/r.univar_main.c
index 454df33..5674489 100644
--- a/raster/r.univar2/r.univar_main.c
+++ b/raster/r.univar2/r.univar_main.c
@@ -184,6 +184,15 @@ process_raster (univar_stat *stats, int fd,
     int first = (stats->n < 1);
 
     RASTER_MAP_TYPE map_type;
+    void *all_values
+	= ((! param.extended->answer) ? 0
+	   : (map_type == DCELL_TYPE) ? stats->dcell_array
+	   : (map_type == FCELL_TYPE) ? stats->fcell_array
+	   : stats->cell_array);
+    size_t value_sz
+	= ((map_type   == DCELL_TYPE) ? sizeof (DCELL)
+	   : (map_type == FCELL_TYPE) ? sizeof (FCELL)
+	   : sizeof (CELL));
     unsigned int row;
     void *raster_row;
 
@@ -206,73 +215,32 @@ process_raster (univar_stat *stats, int fd,
 		continue;
 	    }
 
-
-	    if (map_type == CELL_TYPE) {
-		const int val_i = *((CELL *) ptr);
-
-		stats->sum += val_i;
-		stats->sumsq += (double) val_i * val_i;
-		stats->sum_abs += abs(val_i);
-
-		if (param.extended->answer)
-		    stats->cell_array[stats->n] = val_i;
-
-		if (first) {
-		    stats->max = val_i;
-		    stats->min = val_i;
-		    first = FALSE;
-		}
-		else {
-		    if (val_i > stats->max)
-			stats->max = val_i;
-		    if (val_i < stats->min)
-			stats->min = val_i;
-		}
+	    if (all_values) {
+		/* put the value into stats->XXXcell_array */
+		memcpy (all_values + stats->n * value_sz,
+			ptr, value_sz);
 	    }
-	    else if (map_type == FCELL_TYPE) {
-		const float val_f = *((FCELL *) ptr);
 
-		stats->sum += val_f;
-		stats->sumsq += (double) val_f * val_f;
-		stats->sum_abs += fabs(val_f);
+	    {
+		double val
+		    = ((map_type   == DCELL_TYPE) ? *((DCELL *) ptr)
+		       : (map_type == FCELL_TYPE) ? *((FCELL *) ptr)
+		       : *((CELL *) ptr));
 
-		if (param.extended->answer)
-		    stats->fcell_array[stats->n] = val_f;
+		stats->sum += val;
+		stats->sumsq += val * val;
+		stats->sum_abs += fabs (val);
 
 		if (first) {
-		    stats->max = val_f;
-		    stats->min = val_f;
+		    stats->max = val;
+		    stats->min = val;
 		    first = FALSE;
-		}
-		else {
-		    if (val_f > stats->max)
-			stats->max = val_f;
-		    if (val_f < stats->min)
-			stats->min = val_f;
+		} else {
+		    if (val > stats->max) stats->max = val;
+		    if (val < stats->min) stats->min = val;
 		}
 	    }
-	    else if (map_type == DCELL_TYPE) {
-		const double val_d = *((DCELL *) ptr);
-
-		stats->sum += val_d;
-		stats->sumsq += val_d * val_d;
-		stats->sum_abs += fabs(val_d);
 
-		if (param.extended->answer)
-		    stats->dcell_array[stats->n] = val_d;
-
-		if (first) {
-		    stats->max = val_d;
-		    stats->min = val_d;
-		    first = FALSE;
-		}
-		else {
-		    if (val_d > stats->max)
-			stats->max = val_d;
-		    if (val_d < stats->min)
-			stats->min = val_d;
-		}
-	    }
 	    ptr = G_incr_void_ptr(ptr, G_raster_size(map_type));
 	    stats->n++;
 	}