better decoding of kval_file in writeSpectraPk

src/camel/exec/writeSpectraPk.cc

@@ -201,9 +201,17 @@ int main(int argc,char** argv){
 
   string kvfile=parser.params.find<string>("kval_file","");
   if (kvfile.size()!=0) {
+    cout <<"using k values from file=" <<kvfile <<endl;
+    //decode 1st column
     ifstream f(kvfile.c_str());
+    string line;
     double kk;
-    while (f>>kk) kval.push_back(kk);
+    while (getline(f,line)) {
+      //skip comments
+      if (line.find("#",0) !=std:: string::npos) continue;
+      std::istringstream str(line);
+      if (str>>kk) kval.push_back(kk);
+    }
   }
   else{
   const int npks = parser.params.find<int>("n_pks",1000);