use mhphlus observed given by tandem to compute experimental mass

src/input/xtandemsaxhandler.cpp

@@ -174,6 +174,7 @@ bool XtandemSaxHandler::startElement_file(QXmlAttributes attributes) {
 }
 
 bool XtandemSaxHandler::startElement_domain(QXmlAttributes attributes) {
+    //mh="1120.529471"
 //<domain id="1976.1.1" start="620" end="629" expect="9.7e-04" mh="1120.5307" delta="-0.0012" hyperscore="29.9"
     //nextscore="10.2" y_score="10.4" y_ions="7" b_score="11.2" b_ions="3" pre="QLYR" post="RYGV"
     //seq="AQEEMAQVAK" missed_cleavages="0">
@@ -276,10 +277,14 @@ bool XtandemSaxHandler::startElement_domain(QXmlAttributes attributes) {
     _p_peptide_evidence->setEvalue(attributes.value("expect").simplified().toDouble());
     //qDebug() << "XtandemSaxHandler::startElement_domain evalue "  << _p_peptide_match->getEvalue() << " scan " << _p_peptide_match->getScan();
 
-    pappso::pappso_double xtandem_mhtheo = attributes.value("mh").simplified().toDouble();
+    pappso::pappso_double xtandem_mhtheoretical = attributes.value("mh").simplified().toDouble();
     pappso::pappso_double xtandem_delta = attributes.value("delta").simplified().toDouble();
 
-    pappso::pappso_double exp_mass = xtandem_mhtheo + xtandem_delta - pappso::MHPLUS;
+    //delta – the spectrum mh minus the calculated mh
+    
+    //exp mass computed from X!Tandem mh :
+    pappso::pappso_double exp_mass = _mhplus_obser - pappso::MHPLUS;
+    
 
     _p_peptide_evidence->setExperimentalMass(exp_mass);
     _current_peptide_match.setStart(attributes.value("start").simplified().toUInt()-1);