I have a problem regarding accessing the value of array by pointer. In native C++ language, I can access the element by the following code
int a[]={1,2,3};
cout<<*(a+1);
So, I can get "2".
However, when I use C++ CLR and openCV 2.4.7, there is an error. The code as bellow.
cv::Mat a;
cout<<*(a+1);
I don't know how to deal with it after searching some websites. Wish anyone can help me. Thank you!
when you declare int a[] you should ask yourself what is a?
the answer is: a is array of integers. it is also the address of the first integer in the array.
so when you call *(a+1);
it been interpreted as:
take the address of a and add size of int to it (a+1).
go to the result address and take its content.
when you declare cv::Mat a; it is not an array. a is an object, not an address.
now (a+1) has any meaning only when cv::Mat has the operator +. otherwise it will result an error. even if it has the operator + I'll guess the return value will be a cv::Mat not an integer.
*(a+1) has no meaning since the result is not an address.
And finally ,to print it with a cout it also has to implement the stream operator operator<< with argument of cv::Mat.
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