TRestStringHelper adding UnitConversion method (WIP)

source/framework/tools/inc/TRestStringHelper.h

@@ -20,6 +20,7 @@
 #include <sstream>
 
 #include "TRestStringOutput.h"
+#include "TRestSystemOfUnits.h"
 
 /// String helper classes. Declared static to be able to have direct access to the methods
 namespace REST_StringHelper {
@@ -34,6 +35,7 @@ Double_t StringToDouble(std::string in);
 Int_t StringToInteger(std::string in);
 std::string IntegerToString(Int_t n, std::string format = "%d");
 std::string DoubleToString(Double_t d, std::string format = "%4.2lf");
+std::string UnitConversion(std::string in);
 Bool_t StringToBool(std::string in);
 Long64_t StringToLong(std::string in);
 TVector3 StringTo3DVector(std::string in);

source/framework/tools/src/TRestStringHelper.cxx

@@ -607,6 +607,26 @@ string REST_StringHelper::IntegerToString(Int_t n, std::string format) { return
 ///
 string REST_StringHelper::DoubleToString(Double_t d, std::string format) { return Form(format.c_str(), d); }
 
+///////////////////////////////////////////////
+/// \brief It will transform a string containing units("UNIT"), where UNIT is any REST valid
+/// physical unit, to its corresponding scaling factor.
+///
+std::string REST_StringHelper::UnitConversion(std::string in) {
+    std::string inIn = RemoveWhiteSpaces(in);
+    size_t pos1 = inIn.find("units(\"");
+    if (pos1 != 0) {
+        pos1 = inIn.find("units(\'");
+        if (pos1 != 0) return in;
+    }
+
+    size_t pos2 = in.find(")");
+
+    std::string unit = inIn.substr(7, pos2 - 8);
+    //   std::cout << unit << std::endl;
+
+    return DoubleToString(1. * units(unit));
+}
+
 Bool_t REST_StringHelper::StringToBool(std::string in) {
     return (ToUpper(in) == "TRUE" || ToUpper(in) == "ON");
 }