Building an array of difference values

Dear Forum Members,
With reference to the attached LabVIEW 2010 Student Edition file....
From the incoming data via the .csv 'Read From Spreadsheet' I want to display an array of the difference between the n and n-1 data value i.e. if the data set is 10, 20, 25, 35, 50 then the difference will be 10, 5, 10, 15.
I have used the 'Index Array' function to extract the n and n-1 data values (using the 'Simulation Time' function as the Index Row incrementer) however I cannot find the way to build an array of these difference values and display them in the Front Panel i.e.
10
5
10
15
This will no doubt be a trivial issue for those more experienced LabVIEW programmers. Any advice or assistance will be gratefully received.
Kind regards,
Solved!
Go to Solution.
Attachments:
Plant_Simulator (04-05-2013).vi ‏158 KB

I'll explain what I want to do again for clarity....
I have a simple spreadsheet file (in .csv format) that contains one (1) column of data x 800 rows (thats 800 elements). I read the data into LabVIEW via the 'Read from Spreadsheet' function (I have already established this). I then want to make an array that is the difference beween the n and n-1 data value. Hence if the data set is 10, 20, 25, 50... then the difference will be 10, 5, 25..
I want to display the difference array to screen in an indicator that shows all the difference values in one (1) column x 799 rows. Hopefully that explains what I want to achieve.
I tried the suggestion with the loop however there were multiple errors when this was attempted. I cannot place the loop within the simulation frame (it doesn't allow it) hence its outside.
Please excuse my inexperience concerning the array order(s), I find LabVIEW to be particularly unfriendly in this respect and its the source of much of my frustration and pain whenever I'm using LabVIEW to implement anything.
Regards,

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