• NA (33/33) Jul 08 2014 Hi,
• Tobias Pankrath (1/3) Jul 08 2014 Use std.algorithm.sort with a custom comparison function.
• bearophile (7/8) Jul 08 2014 It's a very nice example of learning algorithms and data fitting.
• Tobias Pankrath (4/11) Jul 08 2014 I had your solution in mind, too, as a hint that the problem
• bearophile (36/37) Jul 08 2014 Is this good enough?
• NA (20/57) Jul 08 2014 Thanks but
• bearophile (43/44) Jul 08 2014 Why no sort?
• NA (6/9) Jul 08 2014 Thanks,
• Tobias Pankrath (2/4) Jul 08 2014 What are you trying to do? To reorder the elements of a sequence

"NA" <NA nospam.com> writes:

Hi,

I have the following array.

[
	[
		[],
		[],
		[[0, 1] [0, 2]],
		[[0, 0] [0, 3]]
	]

	[
		[],
		[],
		[[1, 1] [1, 2]],
		[[1, 0] [1, 3]]
	]
]

and would like it to be arranged like

[
	[
		[[0, 1] [0, 2]],
		[[0, 0] [0, 3]],
		[],
		[]
	]

	[
		[[1, 1] [1, 2]],
		[[1, 0] [1, 3]],
		[],
		[]
	]
]

Any ideas welcome.

NA

"Tobias Pankrath" <tobias pankrath.net> writes:

 Any ideas welcome.

 NA

Use std.algorithm.sort with a custom comparison function.

"bearophile" <bearophileHUGS lycos.com> writes:

Tobias Pankrath:

 Use std.algorithm.sort with a custom comparison function.

It's a very nice example of learning algorithms and data fitting. 
I have shown an answer very fitted (perhaps over-fitted) on the 
given example. With just the given data there is no way to know 
how much general the problem is :-)

Bye,
bearophile

"Tobias Pankrath" <tobias pankrath.net> writes:

On Tuesday, 8 July 2014 at 18:26:20 UTC, bearophile wrote:
 Tobias Pankrath:

 Use std.algorithm.sort with a custom comparison function.

 It's a very nice example of learning algorithms and data 
 fitting. I have shown an answer very fitted (perhaps 
 over-fitted) on the given example.

I had your solution in mind, too, as a hint that the problem 
might be underspecified.

 With just the given data there is no way to know how much 
 general the problem is :-)

Yeah, but I hope at least he knows it.

"bearophile" <bearophileHUGS lycos.com> writes:

NA:

 Any ideas welcome.

Is this good enough?

void main() {
     import std.algorithm: swap;

     int[][][][] a =
         [[[],
           [],
           [[0, 1], [0, 2]],
           [[0, 0], [0, 3]]
          ],
          [[],
           [],
           [[1, 1], [1, 2]],
           [[1, 0], [1, 3]]
          ]
         ];

     int[][][][] b =
         [[[[0, 1], [0, 2]],
           [[0, 0], [0, 3]],
           [],
           [],
          ],
          [[[1, 1], [1, 2]],
           [[1, 0], [1, 3]],
           [],
           []
          ]
         ];

     foreach (s1; a) {
         swap(s1[0], s1[2]);
         swap(s1[1], s1[3]);
     }
     assert(a == b);
}


Bye,
bearophile

"NA" <NA nospam.com> writes:

On Tuesday, 8 July 2014 at 18:16:55 UTC, bearophile wrote:
 NA:

 Any ideas welcome.

 Is this good enough?

 void main() {
     import std.algorithm: swap;

     int[][][][] a =
         [[[],
           [],
           [[0, 1], [0, 2]],
           [[0, 0], [0, 3]]
          ],
          [[],
           [],
           [[1, 1], [1, 2]],
           [[1, 0], [1, 3]]
          ]
         ];

     int[][][][] b =
         [[[[0, 1], [0, 2]],
           [[0, 0], [0, 3]],
           [],
           [],
          ],
          [[[1, 1], [1, 2]],
           [[1, 0], [1, 3]],
           [],
           []
          ]
         ];

     foreach (s1; a) {
         swap(s1[0], s1[2]);
         swap(s1[1], s1[3]);
     }
     assert(a == b);
 }


 Bye,
 bearophile

Thanks but

     int[][][][] a =
         [[[],
           [],
           [],
           [],
           [[0, 1], [0, 2]],
           [[0, 0], [0, 3]]
          ],
          [[],
           [],
           [],
           [],
           [[1, 1], [1, 2]],
           [[1, 0], [1, 3]]
          ]
         ];

will not work and no I can't sort it.

Cheers.

"bearophile" <bearophileHUGS lycos.com> writes:

NA:

 will not work and no I can't sort it.

Why no sort?


void main() {
     import std.algorithm: sort, SwapStrategy;
     import std.array: empty;

     int[][][][] a =
         [[[],
           [],
           [],
           [],
           [[0, 1], [0, 2]],
           [[0, 0], [0, 3]]
          ],
          [[],
           [],
           [],
           [],
           [[1, 1], [1, 2]],
           [[1, 0], [1, 3]]
          ]
         ];

     int[][][][] b =
         [[[[0, 1], [0, 2]],
           [[0, 0], [0, 3]],
           [],
           [],
           [],
           []
          ],
          [[[1, 1], [1, 2]],
           [[1, 0], [1, 3]],
           [],
           [],
           [],
           []
          ]
         ];

     foreach (s1; a)
         s1.sort!(q{ a.empty < b.empty }, SwapStrategy.stable);
     assert(a == b);
}


Bye,
bearophile

"NA" <NA nospam.com> writes:

On Tuesday, 8 July 2014 at 18:40:37 UTC, bearophile wrote:
 NA:

 will not work and no I can't sort it.

 Why no sort?

Thanks,
It works as expected.

As for the sort - wasn't thinking straight.

Cheers,
NA

"Tobias Pankrath" <tobias pankrath.net> writes:

 will not work and no I can't sort it.

 Cheers.

What are you trying to do? To reorder the elements of a sequence 
in a specified manner is called sorting, where I live.