howto resize a 2d array (C++)?

[bignateyk]

How would I resize a 2d array in c++? I googled for it, but couldnt find anything...

I tried using the array.resize command but I couldnt get it to work.

Say I have

double myArray[2][2];

how would I resize that to

myArray[x][y];

Thanks,

-Nate

 

[Oogle]

You need to delete and renew all of x in a for loop. For each x, repeat the same delete/renew process for each y in another for loop. In other words, it's a major PITA. Use a 2d vector. It'll save you a lot of resizing headaches.

 

[glugglug]

If it's declared statically as above, you can't resize it.

You need to instead use a double ** (pointer to pointer to double, a.k.a. array of arrays of doubles)

1. Free unused rows if x > old x.
2. resize the inner arrays to your new y dimension
3. then resize the main array to your new x dimension.
4. allocate inner arrays towards the end of main array if y > old y.

Or as Oogle suggested, you can use a vector<vector<double>>

 

[Barnaby W. Füi]

Yeah, if you're using c++ you really should use the standard library to its fullest potential, vectors and lists and strings and all that.