diff --git a/source/framework/core/src/TRestSystemOfUnits.cxx b/source/framework/core/src/TRestSystemOfUnits.cxx
index a0fbc3e6a..58c69a203 100644
--- a/source/framework/core/src/TRestSystemOfUnits.cxx
+++ b/source/framework/core/src/TRestSystemOfUnits.cxx
@@ -85,7 +85,7 @@ string GetStandardUnitDefinition(string unitsdef) { return units(unitsdef).ToSta
 /// \brief Find and return the units definition in a string
 ///
 /// We suppose the last of **value** before **units** must be "1234567890(),.-".
-/// Hence this prepority can be used to spilt the input string into value part and unit part
+/// Hence this prepority can be used to split the input string into value part and unit part
 /// e.g.
 /// value="(1,-13)mm"
 /// value="-3mm"
@@ -113,7 +113,7 @@ string FindRESTUnitsInString(string s) {
 /// can both be recognized
 ///
 string RemoveUnitsFromString(string s) {
-    string valstr1 = s.substr(0, s.find_first_not_of("1234567890(),.-eE/: "));
+    string valstr1 = s.substr(0, s.find_first_not_of("1234567890(),.-eE/*+: "));
 
     if (valstr1.size() == 0) {
         return "";
@@ -280,7 +280,7 @@ TRestSystemOfUnits::TRestSystemOfUnits(string unitsStr) {
                         orderprefix = -1;
                     } else if (unitsStr[pos1 - 1] == '-' || unitsStr[pos1 - 1] == '*') {
                     } else {
-                        RESTWarning << "illegeal unit combiner \"" << unitsStr[pos1 - 1] << "\"" << RESTendl;
+                        RESTWarning << "illegal unit combiner \"" << unitsStr[pos1 - 1] << "\"" << RESTendl;
                     }
                 }
 
diff --git a/source/framework/tools/src/TRestStringHelper.cxx b/source/framework/tools/src/TRestStringHelper.cxx
index 0d96327b6..59edf2af1 100644
--- a/source/framework/tools/src/TRestStringHelper.cxx
+++ b/source/framework/tools/src/TRestStringHelper.cxx
@@ -97,7 +97,7 @@ string REST_StringHelper::CropWithPrecision(string in, Int_t precision) {
 /// The buffer string may define sub-expressions that will be evaluated by using single quotes.
 ///
 /// I.e. The sentence "The following operation 3 x 4 is '3*4'" will be translated to
-/// "The following operatin 3 x 4 is 12".
+/// "The following operation 3 x 4 is 12".
 ///
 string REST_StringHelper::ReplaceMathematicalExpressions(string buffer, Int_t precision,
                                                          string errorMessage) {
@@ -585,8 +585,9 @@ TRestStringOutput::REST_Verbose_Level REST_StringHelper::StringToVerboseLevel(st
 /// \brief Gets a double from a string.
 ///
 Double_t REST_StringHelper::StringToDouble(string in) {
-    if (isANumber(in)) {
-        return stod(in);
+    std::string out = ReplaceMathematicalExpressions(in, 0);
+    if (isANumber(out)) {
+        return stod(out);
     } else {
         return -1;
     }
@@ -596,8 +597,9 @@ Double_t REST_StringHelper::StringToDouble(string in) {
 /// \brief Gets a float from a string.
 ///
 Float_t REST_StringHelper::StringToFloat(string in) {
-    if (isANumber(in)) {
-        return stof(in);
+    std::string out = ReplaceMathematicalExpressions(in, 0);
+    if (isANumber(out)) {
+        return stof(out);
     } else {
         return -1;
     }