[GRASS-SVN] r69953 - grass-addons/grass7/raster/r.series.lwr

[svn_grass at osgeo.org]

Author: mmetz
Date: 2016-11-30 05:33:13 -0800 (Wed, 30 Nov 2016)
New Revision: 69953

Modified:
   grass-addons/grass7/raster/r.series.lwr/main.c
   grass-addons/grass7/raster/r.series.lwr/r.series.lwr.html
Log:
r.series.lwr: skip large gaps in time

Modified: grass-addons/grass7/raster/r.series.lwr/main.c
===================================================================
--- grass-addons/grass7/raster/r.series.lwr/main.c	2016-11-29 13:34:36 UTC (rev 69952)
+++ grass-addons/grass7/raster/r.series.lwr/main.c	2016-11-30 13:33:13 UTC (rev 69953)
@@ -218,6 +218,7 @@
 		      *weight,	/* weighing function */
 		      *fet,	/* fit error tolerance */
 		      *ts,	/* time steps */
+		      *maxgap,	/* maximum gap size */
 		      *dod,	/* degree of over-determination */
 		      *range,	/* range of valid values */
 		      *delta;	/* threshold for high amplitudes */
@@ -242,7 +243,7 @@
     DCELL *resultn;
     int msize;
     double **m, **m2, *a, *a2, *B;
-    double *ts, weight;
+    double *ts, maxgap, thisgap, prev_ts, next_ts, weight;
     double (*weight_func)(double, double, double);
     int dod;
     int *isnull, n_nulls;
@@ -320,6 +321,11 @@
     parm.ts->multiple = YES;
     parm.ts->description = _("Time steps of the input maps");
 
+    parm.maxgap = G_define_option();
+    parm.maxgap->key = "maxgap";
+    parm.maxgap->type = TYPE_DOUBLE;
+    parm.maxgap->description = _("Maximum gap size to be interpolated");
+
     parm.delta = G_define_option();
     parm.delta->key = "delta";
     parm.delta->type = TYPE_DOUBLE;
@@ -493,6 +499,11 @@
 	}
     }
 
+    maxgap = ts[num_inputs - 1] - ts[0];
+    if (parm.maxgap->answer) {
+	maxgap = atof(parm.maxgap->answer);
+    }
+
     /* open output maps */
     num_outputs = num_inputs;
 
@@ -590,10 +601,42 @@
 
 	    /* LWR */
 	    if (num_inputs - n_nulls >= min_points) {
+		
+		thisgap = 0;
+		prev_ts = next_ts = ts[0] - (ts[1] - ts[0]);
 
 		for (i = first; i <= last; i++) {
 		    DCELL result;
 
+		    if (isnull[i]) {
+			if (next_ts < ts[i]) {
+			    if (i > 0)
+				prev_ts = ts[i] - (ts[i] - ts[i - 1]) / 2.0;
+			    else
+				prev_ts = ts[i] - (ts[i + 1] - ts[i]) / 2.0;
+			    
+			    if (i < num_inputs - 1)
+				next_ts = ts[i] + (ts[i + 1] - ts[i]) / 2.0;
+			    else
+				next_ts = ts[i] + (ts[i] - ts[i - 1]) / 2.0;
+
+			    j = i;
+			    while (j < num_inputs - 1 && isnull[j + 1])
+				j++;
+
+			    if (j > i)
+				next_ts = ts[j] + (ts[j + 1] - ts[j]) / 2.0;
+			    else
+				next_ts = ts[j] + (ts[j] - ts[j - 1]) / 2.0;
+
+			    thisgap = next_ts - prev_ts;
+			}
+			if (thisgap > maxgap) {
+			    Rast_set_d_null_value(&outputs[i].buf[col], 1);
+			    continue;
+			}
+		    }
+
 		    /* margin around i */
 		    n_points = 0;
 		    in_lo = in_hi = i;
@@ -618,7 +661,13 @@
 			    break;
 			}
 		    }
+		    if (interp_only && isnull[i] &&
+		        (in_lo == i || in_hi == i)) {
 
+			Rast_set_d_null_value(&outputs[i].buf[col], 1);
+			continue;
+		    }
+
 		    tsdiff1 = ts[i] - ts[in_lo];
 		    tsdiff2 = ts[in_hi] - ts[i];
 			

Modified: grass-addons/grass7/raster/r.series.lwr/r.series.lwr.html
===================================================================
--- grass-addons/grass7/raster/r.series.lwr/r.series.lwr.html	2016-11-29 13:34:36 UTC (rev 69952)
+++ grass-addons/grass7/raster/r.series.lwr/r.series.lwr.html	2016-11-30 13:33:13 UTC (rev 69953)
@@ -32,6 +32,17 @@
 contains many outliers. A few outliers are handled well with the 
 default settings.
 
+<p>
+Gaps in the time series are by default interpolated, as long as the 
+time series contains sufficient non-NULL points. Optionally, the 
+maximum size of gaps to be interpolated can be set with the 
+<em>maxgap</em> option.
+
+<p>
+Extrapolation can be avoided with the <em>-i</em> flag. In this case, 
+LWR is performed only from the first non-NULL point to the last 
+non-NULL point in the time series.
+
 <h2>NOTES</h2>
 
 If the <em>range</em> option is given, any values which fall outside