[GRASS-SVN] r71054 - grass-addons/grass7/raster/r.seasons

[svn_grass at osgeo.org]

Author: mmetz
Date: 2017-05-07 12:52:36 -0700 (Sun, 07 May 2017)
New Revision: 71054

Modified:
   grass-addons/grass7/raster/r.seasons/main.c
   grass-addons/grass7/raster/r.seasons/r.seasons.html
Log:
r.seasons: add max_gap option

Modified: grass-addons/grass7/raster/r.seasons/main.c
===================================================================
--- grass-addons/grass7/raster/r.seasons/main.c	2017-05-07 18:13:09 UTC (rev 71053)
+++ grass-addons/grass7/raster/r.seasons/main.c	2017-05-07 19:52:36 UTC (rev 71054)
@@ -50,7 +50,8 @@
 }
 
 static int get_season(double *val, char *isnull, double *ts, int i0,
-                      int n, double threshold, double minlen,
+                      int n, double threshold,
+		      double minlen, double maxgap,
 		      int *start1, int *start2,
 		      int *end1, int *end2)
 {
@@ -113,7 +114,7 @@
 	    else
 		blenout -= ts[i] - (ts[i + 1] - ts[i]) / 2.0;
 	    
-	    if (blenout >= minlen)
+	    if (blenout >= maxgap)
 		break;
 	}
     }
@@ -159,7 +160,7 @@
 	    else
 		blenout -= ts[startout] - (ts[startout + 1] - ts[startout]) / 2.0;
 	    
-	    if (blenout >= minlen)
+	    if (blenout >= maxgap)
 		break;
 	}
     }
@@ -177,7 +178,8 @@
 		      *ns,		/* number of seasons */
 		      *nsout,		/* output map for number of seasons */
 		      *threshold,	/* threshold to start/stop a season */
-		      *min;		/* minimum length in time to recognize a start/stop event */
+		      *min,		/* minimum length in time to recognize a season */
+		      *max;		/* maximum length in time to separate two seasons */
     } parm;
     struct
     {
@@ -195,7 +197,7 @@
     DCELL *values = NULL;
     int nrows, ncols;
     int row, col;
-    double minlen;
+    double minlen, maxgap;
     int ns, nsmax, nfound;
     double threshold;
     double *ts;
@@ -253,12 +255,19 @@
     parm.threshold->description = _("Threshold to start/stop a season");
 
     parm.min = G_define_option();
-    parm.min->key = "min";
+    parm.min->key = "min_length";
     parm.min->type = TYPE_DOUBLE;
     parm.min->required = YES;
-    parm.min->label = _("Minimum number of time steps");
+    parm.min->label = _("Minimum season length");
     parm.min->description = _("A season must be at least min long, otherwise the data are considered as noise");
 
+    parm.max = G_define_option();
+    parm.max->key = "max_gap";
+    parm.max->type = TYPE_DOUBLE;
+    parm.max->required = NO;
+    parm.max->label = _("Maximum gap length (default: min_length)");
+    parm.max->description = _("A gap must not be longer than max, otherwise the season is terminated");
+
     flag.lo = G_define_flag();
     flag.lo->key = 'l';
     flag.lo->description = _("Stop a season when a value is above threshold (default: below threshold");
@@ -288,6 +297,14 @@
     minlen = atof(parm.min->answer);
     if (minlen <= 0)
 	G_fatal_error(_("Minimum season length must be positive"));
+
+    maxgap = minlen;
+    if (parm.max->answer) {
+	maxgap = atof(parm.max->answer);
+	if (maxgap <= 0)
+	    G_fatal_error(_("Maximum gap length must be positive"));
+    }
+
     threshold = atof(parm.threshold->answer);
 
     if (flag.lo->answer)
@@ -470,7 +487,8 @@
 	    nfound = 0;
 	    i0 = 0;
 	    while (get_season(values, isnull, ts, i0, num_inputs,
-		  threshold, minlen, &start1, &start2, &end1, &end2)) {
+		              threshold, minlen, maxgap,
+			      &start1, &start2, &end1, &end2)) {
 
 		i0 = end2 + 1;
 

Modified: grass-addons/grass7/raster/r.seasons/r.seasons.html
===================================================================
--- grass-addons/grass7/raster/r.seasons/r.seasons.html	2017-05-07 18:13:09 UTC (rev 71053)
+++ grass-addons/grass7/raster/r.seasons/r.seasons.html	2017-05-07 19:52:36 UTC (rev 71054)
@@ -1,22 +1,25 @@
 <h2>DESCRIPTION</h2>
 
 <em>r.seasons</em> counts the number of seasons in a time series. A 
-season is defined as a time period of at least <em>min</em> length 
-where no value is below <em>threshold</em> (with the <em>-l</em> flag, 
-no value above <em>threshold</em>).
+season is defined as a time period of at least <em>min_length</em> 
+length where no value is below <em>threshold</em> (with the <em>-l</em> 
+flag, no value above <em>threshold</em>).
 
 <p>
 The <em>nout</em> output holds the number of detected seasons. Output 
 raster maps with the start and end dates of each season are produced 
-for at most <em>n</em> number of seasons. For each season, two start 
-dates and two end dates are determined. The start date start1 and the 
-end date end1 indicate the start and end of the core season, while the 
-start date start2 and the end date end2 indicate the start and end of 
-the full season including some gaps at the beginning and end of the 
-season. Gaps are shorter than <em>min</em>, that is, a season will not 
-include gaps equal or longer than <em>min</em>.
+for at most <em>n</em> number of seasons.
 
+<p>
+For each season, two start dates and two end dates are determined. The 
+start date start1 and the end date end1 indicate the start and end of 
+the core season, while the start date start2 and the end date end2 
+indicate the start and end of the full season including some gaps at 
+the beginning and end of the season. Gaps are shorter than 
+<em>max_gap</em>, that is, a season will not include gaps equal or 
+longer than <em>max_gap</em>.
 
+
 <h2>NOTES</h2>
 
 The maximum number of raster maps that can be processed is given by the 
@@ -95,7 +98,7 @@
 
 <div class="code"><pre>
 r.seasons input=`g.list rast pat=MOD13* sep=,` prefix=ndvi_season n=3 \
-  nout=ndvi_season threshold=3000 min=6
+  nout=ndvi_season threshold=3000 min_length=6
 
 # the outputs are: 
 g.list type=raster pattern=ndvi_season*