How to dynamically create a c++ array with known 2nd dimension? -


i have function:

void foo(double[][4]);

which takes 2d array 2nd dimension equal 4. how allocate 2d array can pass function? if this:

double * arr[4]; arr = new double[n][4];

where n not known compiler. cannot compile. if use generic 2d dynamic array, function foo not take it.

as asked, best use typedef

 typedef double four[4];  4 *arr;     // equivalently double (*arr)[4];  arr = new four[n];

without typedef more cryptic

double (*arr)[4]; arr = new double [n][4];

you should consider using standard containers (std::vector, etc) or containers of containers though.


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