[SNAP-1551] Improve binning documentation about spatial data-day

(cherry picked from commit 52fca76)
senbox-org · Aug 19, 2022 · 81c54df · 81c54df
1 parent e10130f
commit 81c54df
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Showing 2 changed files with 6 additions and 3 deletions.
diff --git a/snap-binning/src/main/java/org/esa/snap/binning/operator/BinningOp.java b/snap-binning/src/main/java/org/esa/snap/binning/operator/BinningOp.java
@@ -176,8 +176,8 @@ public enum TimeFilterMethod {
 
     @Parameter(interval = "[0,24]",
             description = "A sensor-dependent constant given in hours of a day (0 to 24)\n" +
-                          "at which a sensor has a minimum number of observations at the date line (the 180 degree meridian).\n" +
-                          "Only used if parameter 'dataDayMode' is set to 'SPATIOTEMPORAL_DATADAY'.")
+                    "at which a sensor has a minimum number of observations at the date line (the 180 degree meridian).\n" +
+                    "Only used if parameter 'dataDayMode' is set to 'SPATIOTEMPORAL_DATADAY'. This is usually the equator crossing time (ECT)")
     private Double minDataHour;
 
     @Parameter(description = "Number of rows in the (global) planetary grid. Must be even.", defaultValue = "2160")

diff --git a/snap-binning/src/main/java/org/esa/snap/binning/support/SpatialDataPeriod.java b/snap-binning/src/main/java/org/esa/snap/binning/support/SpatialDataPeriod.java
@@ -20,6 +20,8 @@
 
 /**
  * The definition of a "spatial data-day", or more generally, a spatial data-period used for the binning.
+ * A detailed description of this period definition can be found in
+ * the <a href="https://www.globcolour.info/CDR_Docs/GlobCOLOUR_PUG_v4.1.pdf">GlobColour PUG in section 3.4 "The GlobColour data-day approach"</a>.
  *
  * @author Norman Fomferra
  */
@@ -37,7 +39,8 @@ public class SpatialDataPeriod implements DataPeriod {
      * @param duration    The binning period's duration in days.
      * @param minDataHour The time in hours of a day (0 to 24) at which a given sensor has a minimum number of observations at the date line (the 180deg meridian).
      *                    This number is usually found plotting longitude-time pairs of given sensor observations and then finding
-     *                    the area where there are a minimum number of observations at the date line.
+     *                    the area where there are a minimum number of observations at the date line. This is the crossing nodal time (CNT),
+     *                    which is equal to the equator crossing time (ECT)
      */
     public SpatialDataPeriod(double startTime, double duration, double minDataHour) {
         this.startTime = startTime;