Add a matrix of 2x2 into a vector in c++ -


i trying fill vector matrix of values in c++. i'm not self confident procedure (i don't know pointers , don't know if need here) trying this

int auxmat[gray.rows][gray.cols]; vector<int> collectionsum; collectionsum.push_back(auxmat);

when try compile receive error says

invalid arguments 'candidates are: void push_back(const int &)

can tell me wether it's possible do, how can solve it?

i read erasing cache memory, changing eclipse compiler, c++ version, don't think problem big.

you cannot push matrix vector. can preallocate memory vector (for speeding things up) use std::vector<>::assign member function "copy" matrix vector:

vector<int> collectionsum(gray.rows * gray.cols); // reserve memory, faster collectionsum.assign(*auxmat, *auxmat + gray.rows * gray.cols);

this should pretty fast. otherwise, can push each individual element in loop.

edit

see may treat 2d array contiguous 1d array? technicalities regarding possible undefined behaviour (thanks @juanchopanza comment). believe code safe, due fact storage of matrix contiguous.


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