Changeset 551 for trunk/src

Timestamp:

03/10/05 13:54:16 (20 years ago)

Author:

vor010

Message:

Small improvements in the line finder. Most probably users will not notice them at all. Line wings are now detected better
for strong lines.

File:

• trunk/src/SDLineFinder.cc (modified) (7 diffs)

trunk/src/SDLineFinder.cc

@@ -147 +147 @@
                                            // (pair: start and stop+1 channel)
    RunningBox *running_box;                // running box filter
+   casa::Vector<Int> signs;                // An array to store the signs of
+                                           // the value - current mean
+                                           // (used to search wings)
 public:
 
@@ -157 +160 @@
    // replace the detection criterion
    void setCriterion(int in_min_nchan, casa::Float in_threshold) throw();
+
+   // return the array with signs of the value-current mean
+   // An element is +1 if value>mean, -1 if less, 0 if equal.
+   // This array is updated each time the findLines method is called and
+   // is used to search the line wings
+   const casa::Vector<Int>& getSigns() const throw();
 
    // find spectral lines and add them into list
@@ -417 +426 @@
       throw AipsError(String("LFAboveThreshold::processCurLine - STL error: ")+ex.what());
   }
+}
+
+// return the array with signs of the value-current mean
+// An element is +1 if value>mean, -1 if less, 0 if equal.
+// This array is updated each time the findLines method is called and
+// is used to search the line wings
+const casa::Vector<Int>& LFAboveThreshold::getSigns() const throw()
+{
+  return signs;
 }
 
@@ -459 +477 @@
       // actual search algorithm
       is_detected_before=False;
-      Vector<Int> signs(spectrum.nelements(),0);
+
+      // initiate the signs array
+      signs.resize(spectrum.nelements());
+      signs=Vector<Int>(spectrum.nelements(),0);
 
       //ofstream os("dbg.dat");
@@ -694 +715 @@
                     // instead, min_nchan is also scaled
                     // it helps to search for broad lines
+  Vector<Int> signs; // a buffer for signs of the value - mean quantity
+                     // see LFAboveThreshold for details
+                     // We need only signs resulted from last iteration
+                     // because all previous values may be corrupted by the
+                     // presence of spectral lines
   while (true) {
      // a buffer for new lines found at this iteration
@@ -702 +728 @@
          LFAboveThreshold lfalg(new_lines,avg_factor*min_nchan, threshold);
          lfalg.findLines(spectrum,temp_mask,edge,max_box_nchan);
+         signs.resize(lfalg.getSigns().nelements());
+         signs=lfalg.getSigns();
          first_pass=False;
          if (!new_lines.size())
@@ -725 +753 @@
      temp_mask=getMask();     
   }
+  
+  // an additional search for wings because in the presence of very strong
+  // lines temporary mean used at each iteration will be higher than
+  // the true mean
+  
+  if (lines.size())
+      LFLineListOperations::searchForWings(lines,signs,mask,edge);
+      
   return int(lines.size());
 }