# What is the name of this array transformation?

Start with an array of arrays; in this case, they are different lengths in order to demonstrate the technique, but they do not have to be.

``````[[1,2,3,4], [5,6,7], [8,9,10], [11,12,13,14,15]]
``````

At the other end of the transformation, you have an array of arrays where the first array contains the first element from each of the original arrays, the second array contains the second element from each of the original arrays, and so on.

``````[[1,5,8,11], [2,6,9,12], [3,7,10,13], [4,14], [15]]
``````

Is there a mathematical or CS term for this operation?

## 1 Answer

It's called transposing except for the deal with the flaggedness of the arrays

In linear algebra, the transpose of a matrix A is another matrix AT... created by any one of the following equivalent actions:

• reflect A over its main diagonal (which runs from top-left to bottom-right) to obtain AT
• write the rows of A as the columns of AT
• write the columns of A as the rows of AT

• I feel like I should have recalled this from a math class, but alas, that was some time ago. Thanks. Jul 1, 2013 at 1:27
• Do you mean "raggedness"? Jul 1, 2013 at 2:08