[GRASS-SVN] r52061 - grass-addons/grass7/raster/r.gdd

[svn_grass at osgeo.org]

Author: mmetz
Date: 2012-06-13 09:29:53 -0700 (Wed, 13 Jun 2012)
New Revision: 52061

Modified:
   grass-addons/grass7/raster/r.gdd/main.c
   grass-addons/grass7/raster/r.gdd/r.gdd.html
Log:
r.gdd: fix Winkler index

Modified: grass-addons/grass7/raster/r.gdd/main.c
===================================================================
--- grass-addons/grass7/raster/r.gdd/main.c	2012-06-13 14:18:16 UTC (rev 52060)
+++ grass-addons/grass7/raster/r.gdd/main.c	2012-06-13 16:29:53 UTC (rev 52061)
@@ -153,6 +153,10 @@
 
     baseline = atof(parm.baseline->answer);
     cutoff = atof(parm.cutoff->answer);
+    
+    if (cutoff <= baseline)
+        G_fatal_error(_("'%s' must be > '%s'"), parm.cutoff->key,
+	                                        parm.baseline->key);
 
     if (parm.input->answer && parm.file->answer)
         G_fatal_error(_("input= and file= are mutually exclusive"));
@@ -278,11 +282,11 @@
 
 	for (col = 0; col < ncols; col++) {
 	    int null = 0, non_null = 0;
-	    FCELL min, max, sum, gdd;
+	    FCELL min, max, avg, gdd;
 
 	    min = fnull;
 	    max = fnull;
-	    sum = 0;
+	    avg = 0;
 
 	    for (i = 0; i < num_inputs; i++) {
 		FCELL v = inputs[i].buf[col];
@@ -295,13 +299,8 @@
 			null = 1;
 		    }
 		    else {
-			if (v < baseline)
-			    v = baseline;
-			if (v > cutoff)
-			    v = cutoff;
-
 			if (flag.avg->answer)
-			    sum += v;
+			    avg += v;
 			else {
 			    if (Rast_is_f_null_value(&min) || min > v)
 				min = v;
@@ -321,10 +320,28 @@
 	    }
 	    else {
 
-		if (flag.avg->answer)
-		    gdd = sum / non_null - baseline;
-		else
+		if (flag.avg->answer) {
+		    avg /= non_null;
+
+		    if (avg < baseline)
+			avg = baseline;
+		    if (avg > cutoff)
+			avg = cutoff;
+
+		    gdd = avg - baseline;
+		}
+		else {
+		    if (min < baseline)
+			min = baseline;
+		    if (min > cutoff)
+			min = cutoff;
+		    if (max < baseline)
+			max = baseline;
+		    if (max > cutoff)
+			max = cutoff;
+
 		    gdd = (min + max) / 2. - baseline;
+		}
 
 		if (gdd < 0.)
 		    gdd = 0.;

Modified: grass-addons/grass7/raster/r.gdd/r.gdd.html
===================================================================
--- grass-addons/grass7/raster/r.gdd/r.gdd.html	2012-06-13 14:18:16 UTC (rev 52060)
+++ grass-addons/grass7/raster/r.gdd/r.gdd.html	2012-06-13 16:29:53 UTC (rev 52061)
@@ -1,13 +1,14 @@
 <h2>DESCRIPTION</h2>
 
-<em>r.gdd</em> calculates (accumulated) growing degree days (GDDs) from 
-several input maps with temperature data for different times of the day.
+<em>r.gdd</em> calculates (accumulated) growing degree days (GDDs) and 
+Winkler indices from several input maps with temperature data for 
+different times of the day.
 <p>
 The formula for calculating GDDs is
 <div class="code"><pre>
     gdd = (max + min) / 2 - baseline
 </pre></div>
-or using the average from all input maps
+The formula for calculating the Winkler index is
 <div class="code"><pre>
     gdd = average - baseline
 </pre></div>
@@ -16,13 +17,18 @@
 temperature. The <em>min</em>, <em>max</em> and <em>average</em> values 
 are automatically calculated from the input temperature maps.
 <p>
-Negative GDD values are set to 0 (zero). All (scaled and shifted) 
-temperature values above the <em>cutoff</em> value are set to 
-<em>cutoff</em>, and all (scaled and shifted) temperature values below 
-the <em>baseline</em> value are set to <em>baseline</em>.
+The <em>shift</em> and <em>scale</em> values are applied directly to the 
+input values. The <em>baseline</em>, <em>cutoff</em>, and <em>range</em> 
+options are applied to the shifted and scaled values.
 <p>
-If an existing GDD map is provided with the <em>gdd</em> option, the 
-values of this GDD map are added to the output, thus accumulating GDDs.
+Any <em>min</em>, <em>max</em> and <em>average</em> temperature values 
+above the <em>cutoff</em> value are set to <em>cutoff</em>, and any 
+<em>min</em>, <em>max</em> and <em>average</em> values below the 
+<em>baseline</em> value are set to <em>baseline</em>. Negative results 
+are set to 0 (zero). 
+<p>
+If an existing map is provided with the <em>gdd</em> option, the 
+values of this map are added to the output, thus accumulating GDDs.
 
 <h2>NOTES</h2>