libtsxx [WP][FEATURE]: provide function TimeSeriesCollection::overlap

src/libs/libtsxx/tscollection.h

@@ -80,6 +80,27 @@ namespace ts {
        *         of time series headers in the collection
        */
       bool are_consistent(const ::sff::WID2compare comparer) const;
+      
+      /*! \brief Check is all time series have a common time window
+       *
+       * Check whether all time series overlap in time. This is a necessary
+       * prerequisite for trimming all time series to a common time window.
+       *
+       * \return true, if time series overlap
+       */
+      bool overlap() const;
+      
+      /*! \brief Trim to same start time
+       *
+       * Check the consistency of the time series in the collections based on
+       * header data. For example this can be used to check whether all time
+       * series have the same number of samples.
+       *
+       * \param comparer defines the header fields to be compared
+       * \return true, if comparer returns true for comparison of all pairs
+       *         of time series headers in the collection
+       */
+      bool trim_to_date(const ::sff::WID2compare comparer) const;
 
   }; // class TimeSeriesCollection
 
@@ -103,6 +124,36 @@ namespace ts {
       return(retval);
     } // bool TimeSeriesCollection<T>::are_consistent(const ::sff::WID2compare comparer) const
 
+  /* ---------------------------------------------------------------------- */
+
+  template<typename T>
+    bool TimeSeriesCollection<T>::overlap() const
+    {
+      bool retval=true;
+      if (this->size() > 1)
+      {
+        typename Tbase::const_iterator i_series=this->begin();
+        Theader header=i_series->header;
+        libtime::TAbsoluteTime begin=header.date;
+        libtime::TRelativeTime dt=libtime::double2time(header.dt);
+        libtime::TAbsoluteTime end=header.date+(dt*(header.nsamples-1));
+        ++i_series;
+        while ((i_series != this->end()) && retval)
+        {
+          header=i_series->header;
+          libtime::TAbsoluteTime thisbegin=header.date;
+          libtime::TRelativeTime thisdt=libtime::double2time(header.dt);
+          libtime::TAbsoluteTime thisend=
+            header.date+(thisdt*(header.nsamples-1));
+          begin = thisbegin > begin ? thisbegin : begin;
+          end = thisend < end ? thisend : end;
+          ++i_series;
+        }
+        retval=(end >= begin);
+      }
+      return(retval);
+    } // bool TimeSeriesCollection<T>::overlap() const
+
 } // namespace ts
 
 #endif // TS_TSCOLLECTION_H_VERSION (includeguard)