PCARMSD: added SQUARE_ROOT as synonimous of SQUARE-ROOT

src/colvar/PCARMSD.cpp

@@ -76,6 +76,7 @@ void PCARMSD::registerKeywords(Keywords& keys) {
   keys.addOutputComponent("eig","default","the projections on each eigenvalue are stored on values labeled eig-1, eig-2, ...");
   keys.addOutputComponent("residual","default","the distance of the present configuration from the configuration supplied as AVERAGE in terms of MSD after optimal alignment ");
   keys.addFlag("SQUARED-ROOT",false," This should be setted if you want RMSD instead of MSD ");
+  keys.addFlag("SQUARED_ROOT",false," Same as SQUARED-ROOT");
 }
 
 PCARMSD::PCARMSD(const ActionOptions&ao):
@@ -88,6 +89,7 @@ PCARMSD::PCARMSD(const ActionOptions&ao):
   string f_eigenvectors;
   parse("EIGENVECTORS",f_eigenvectors);
   bool sq;  parseFlag("SQUARED-ROOT",sq);
+  if(!sq) parseFlag("SQUARED_ROOT",sq);
   if (sq) { squared=false; }
   checkRead();