add const and non-const operator[] for RMatrix class

Author: jjallaire

NEWS

@@ -2,6 +2,7 @@ RcppParallel 4.3.9
 ------------------------------------------------------------------------
 
 * Add support for TBB on Solaris
+* Add const and non-const operator[] for RMatrix class
 
 RcppParallel 4.3.8
 ------------------------------------------------------------------------

inst/include/RcppParallel/RMatrix.h

@@ -239,6 +239,14 @@ class RMatrix {
       return Column(*const_cast<RMatrix*>(this), i);
    }
 
+   inline T& operator[](std::size_t i) {
+      return *(data_ + i);
+   }
+   
+   inline const T& operator[](std::size_t i) const {
+      return *(data_ + i);
+   }
+   
 private:
    T* data_;
    std::size_t nrow_;