add fucntions

src/field.h

@@ -191,6 +191,11 @@ public:
 
   void setMissValue(double value);
   double getMissValue() const;
+
+  bool empty() const;
+
+  size_t getNumMiss() const;
+  void setNumMiss(const size_t value);
 };
 
 /************************************************

src/field_t.inl

@@ -102,4 +102,16 @@ inline double Field_t::getMissValue() const {
     return field_operation([](LambdaField_T_ field){return field.getMissValueDouble();}, *this);
 }
 
+inline bool Field_t::empty() const {
+    return field_operation([](LambdaField_T_ field){return field.empty();}, *this);
+}
+
+inline size_t Field_t::getNumMiss() const {
+    return field_operation([](LambdaField_T_ field){return field.nmiss;}, *this);
+}
+
+inline void Field_t::setNumMiss(const size_t value) {
+    return field_operation([](LambdaField_T_ field, const size_t value) {field.nmiss = value;}, *this, value);
+}
+
 #endif // FIELD_t_INL
\ No newline at end of file