improved the nonlocal field dump, by allowing a custom range.

src/external/Nonlocal/prog/dump_nonlocal_field.cpp

@@ -52,6 +52,7 @@ void dnlf_syntax()
   std::cout << "usage: dump_nonlocal_field [<msr-file> --out <field-dump> [--step <stepVal>] | --version | --help]" << std::endl;
   std::cout << "   <msr-file> : nonlocal msr-file name." << std::endl;
   std::cout << "   --out <field-dump> : ascii field dump output file name." << std::endl;
+  std::cout << "   --range <rangeVal> : this optional parameter (in nm) will overwrite the standard z-range = 5 * lambdaL." << std::endl;
   std::cout << "   --step <stepVal>   : this optional parameters allows to define the z-value step size in (nm)." << std::endl;
   std::cout << "   --version          : dumps the version" << std::endl;
   std::cout << "   --help             : will dump this help" << std::endl;
@@ -184,7 +185,8 @@ int main(int argc, char* argv[])
 {
   std::string msrFileName("");
   std::string outFileName("");
-  double step(0.0);
+  double step{0.0};
+  double range{0.0};
   bool show_syntax(false);
 
   if (argc == 1) {
@@ -214,6 +216,22 @@ int main(int argc, char* argv[])
         show_syntax = true;
         break;
       }
+    } else if (!strcmp(argv[i], "--range")) {
+      if (i < argc-1) {
+        try {
+          range = std::stod(argv[i+1]);
+        }
+        catch(std::exception& e) {
+          std::cout << "dump_nonlocal_field: **ERROR** <rangeVal> '" << argv[i+1] << "' seems not to be a double." << std::endl;
+          show_syntax = true;
+          break;
+        }
+        i++;
+      } else {
+        std::cerr << std::endl << "dump_nonlocal_field: **ERROR** found option --range without <rangeVal>" << std::endl;
+        show_syntax = true;
+        break;
+      }
     } else if (!strcmp(argv[i], "--step")) {
       if (i < argc-1) {
         try {
@@ -269,13 +287,15 @@ int main(int argc, char* argv[])
   bool done(false);
   double deadLayer = param[8];
   double b0 = param[6];
+  if (range == 0.0)
+    range = 5.0*param[5]; // 5*lambda
   do {
     if (z < deadLayer) {
       fout << z << ", " << b0 << std::endl;
     } else {
       field = pip.GetMagneticField(z-deadLayer);
       fout << z << ", " << b0*field << std::endl;
-      if (fabs(prevField-field) < 1.0e-10)
+      if ((fabs(prevField-field) < 1.0e-10) && (z >= range))
         done = true;
       prevField = field;
     }