Help!!! Subtract Current value with Previous Value

[neiviv]

Hello, all expert there.

Please help me to solve this simple but look complicated to me because i am not too familiar in using array (other method will do).

With 2 input number added together and stored into an 1D array everytime after i have pressed a button (inside a while loop), i would like to subtract the current value

with the previous value and display it(non array).

It's sound easy but it did take me quite soemtime to do it but still facing a lot of difficulties.

Please help me to solve this. Thanks for your help.

[smercurio_fc]

What have you tried so far? If i understood you correctly, I'm assuming you have a shift register for your array. Since you're adding to the array all you need to do is index out the last element, which is the "previous" element after you've added the "current" element. Then, it's a simple subtraction:



Note that, technically, in the first iteration the indexing is undefined since the array is empty. This may not be an issue for you, though.


Message Edited by smercurio_fc on 02-20-2008 09:01 AM

[JB]

You must use a shift register. See attached example.

[JB]

And if you really need all the sums in an array...

[neiviv]

Thanks for your helps.

btw, JB, i cant open ur VI since i am using LABview 8.0. there is an error on opening the VI. can printscreen the b.diagram for me.

Thanks alot.

[JB]

It takes less time to save them to LV8.0...

[neiviv]

Thanks a lot JB. Thats wat i need.

Thank you as well smercurio_fc, it did help me.

Thanks.