C++ Tip : Treating a Vector as an Array
in [Matlab]
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From: Learn By on 22 Jul 2010 03:00 http://learnbyexamples.org Suppose you have a vector of int and function that takes int *. To obtain the address of the internal array of the vector v and pass it to the function, use the expressions &v[0] or &*v.front(). For example: view plaincopy to clipboardprint? void func(const int arr[], size_t length ); int main() { vector vi; //.. fill vi func(&vi[0], vi.size()); } It’s safe to use &vi[0] and &*v.front() as the internal array’s address as long as you adhere to the following rules: First, func() shouldn’t access out-of-range array elements. Second, the elements inside the vector must be contiguous. Although the C++ Standard doesn’t guarantee that yet, I’m not aware of any implementation that doesn’t use contiguous memory for vectors. Furthermore, this loophole in the C++ Standard will be fixed soon. http://learnbyexamples.org/cc/c-tip-treating-a-vector-as-an-array.html
From: Jan Simon on 22 Jul 2010 12:11 Dear Offtopic poster, > http://[snip] .... Furthermore, this loophole in the C++ Standard will be fixed soon. > http://[snip]/cc/c-tip-treating-a-vector-as-an-array.html I am very happy that this loophole is fixed in Matlab already. I do have the impression, that you want users to click on the link you have posted two times. I won't do this. Jan
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