For loop/formula node/shift register_Beginner question

[s.steen]

Hello,

I'm a Labview beginner and have a beginner question. I think it's for most of u very easy, so please try to help me soon:)

I have (X,Y) datavalues.. I calculated the arithmetic mean using a formula node and a for loop and got (X',Y') out. Now, I want to take the output X' and Y' and calculate a mean value in reference to X and Y. So, the same calculation in the for loop but i want to take the output values and feed it in again as input values. This should be performed N times and plotted.

I tried to use shift registers, but failed to connect it correctly that i can get what I want. I attached here this part of my vi where I have the problem. I hope that you can help me. thanks in advance.

[GerdW]

Hi Sarah,

what's the reason to use formula nodes at all for such simple calculations?

You don't even need FOR loops - see attachment…

but i want to take the output values and feed it in again as input values.

Please define the next step(s): which values should be averaged in the 3rd/4th step?

Do you want to average X'' with X', then X''' with X''?

Or do you want to average X'' with X, then X''' with X?

[s.steen]

thank you so much for ur reply!!

I want to average:

X with X' to get X''

X with X'' to get X'''

X with X''' to get X''''

.. and so on.

this means, I want to take this output eachtime and feed it in one of the inputs.

[GerdW · Accepted solution]

Hi Sarah,

so you need to put the X''-arrays into a shift register, while the original X array stays constant:

[s.steen]

Hello,

thank you again. I tried it similarily before, but it doesn't work correctly, because I want to set N iterations ´for example 3 iterations, to get the average values of the whole input arrays, not only the first 5 values.

for N = 3, I have to get for example:
X''''(0), X''"(1), X''''(2),...X''''(n), where n is the size of the input array

[s.steen]

Hello,

thank you again. I tried it similarily before, but it doesn't work correctly, because I want to set N iterations for example 3 iterations, to get the average values of the whole input arrays, not only the first 5 values.

for N = 3, I have to get for example:
X''''(0), X''"(1), X''''(2),...X''''(n), where n is the size of the input array

[GerdW]

Hi Sarah,

but it doesn't work correctly

What is "it" and where doesn't it work? What is the exact problem?

I want to set N iterations for example 3 iterations, to get the average values of the whole input arrays, not only the first 5 values.

My snippet generates averages for the whole array, so what's your problem?

Did you check the resulting 2D arrays?

[s.steen]

[s.steen]

The resulting 2D Array is fine. I want to set N iterations for taking the output X'' as an input X' and perform this for the whole array. For N=1, an array of 2529 elements. 2 for loops?

[GerdW]

Hi Sarah,

there is a clear difference between my snippet and yours! Do you spot this?

Hint: check the inputs of the FOR loop!