Splitting up an array

[DanB1983]

Fairly simple task, but too early in the morning / late in the week....  usual excuses.

I have a large array of samples (let's call it array X) that I want to split up into several smaller arrays.  I have a second array (let's call it array Y) that contains the indeces to where I would like the splits to occur in the array X.  These indeces will always be in ascending order.

Furthermore, I need to delete the +/-5 elements in array X either side of where the split happens.  So, for each split defined in array Y, I want to delete 11 elements in array X, as well as perform the split.

Once the splits and deletions have occurred, I would like to pack the resulting fragments of array X into a 2D array.

If there are no splits (i.e. array Y is empty), then I simply repack the original array X as a 2D array with one of the dimensions equal to 1.  This is shown in the attached "no_splits.png".

If there is one split, then I perform the split and deletion as described above and pack the resulting 2 parts of array X into a 2D array.  This is shown in the attached "1_split.png".

In the attached PNGs, the integer array is array Y and the 1D double array is array X. 

My issue occurs when there are N splits.  Clearly I need to use a FOR loop, and perform the split and deletion routine N times, feeding back the remaining part of array X each time.  However, I can't for the life of me get this to work - clearly I need to compensate for the offset incurred by the deletion of each successive portion of array X when using the values in array Y to index the next split location.

Any suggestions welcome.  Let me know if more clarification is needed.

Dan

[DavidU]

How about something like this.

Note that the columns in the resulting 2D array get padded with 0s if the splits are not the same length. Also, if a split occurs within 5 points of the preceding split the whole column is padded with 0's.

Dave

Edit: replaced attached vi.

Message Edited by DavidU on 09-03-2009 11:51 AM

[DavidU]

just noticed that my original vi only removes 4 points from the start of each split becasue I didn't take into account the split point itself. I've fixed this in the attached vi by adding a +1 primitive in the loop.

Dave