After finding out the hard way that clone() does not work as intended for multidimensional arrays, now I write
for(int k = 0; k < Nz; k++){
for(int j = 0; j < Ny; j++){
for(int i = 0; i < Nx; i++){
grid_copy[i][j][k] = grid[i][j][k];
}
}
}
for every array. This feels so depressingly low level and anti DRY. Could anyone suggest a more general way of doing this?
If you really really want a generic copier, I just whipped this up here and did some basic testing. It's interesting but I don't think it's any better because what you gain in flexibility is lost in readability.
private void copy(Object source, Object dest) {
if(source.getClass().isArray() && dest.getClass().isArray()) {
for(int i=0;i<Array.getLength(source); i++) {
if(Array.get(source, i) != null && Array.get(source, i).getClass().isArray()) {
copy(Array.get(source, i), Array.get(dest, i));
} else {
Array.set(dest, i, Array.get(source, i));
}
}
}
}
This official tutorial explains how to use the arraycopy method to efficiently copy data from one array into another. I think it works only for one-dimensional arrays, but you can use it to copy the various "blocks of one-dimensional array" contained within your three-dimensional grid. You may find it useful!
I am not aware of a more general way of doing this. I would simply define a function to do it.
public void copyMultidimensionalArray(int[][][] destination,int[][][] source)
{
// your above code here
}
And then I would simply call that function each time.
copyMultidimensionalArray(grid_copy,grid);
Can't get more elegant than that, can I?
Note that the above example is only using integer arrays. You could of course make it more generic using arrays of type Object.
