Formula node for array

hi
i want to convert the values of an array using a different formula for each value in the array. Can i use formula node for this? if yes how
if no then is there any other method except for extracting each one individually and converting?

kunal227 wrote:
there are 16 elements in the array and the number remains constant (actually they are temp values acquired by a fieldpoint hardware).
the formula is a linear conversion (for example y = m*x + C) corresponding to the calibration curve of individual thermocouple connected to the fieldpoint hardware. every thermocouple has a different calibration curve and hence every element in the array is converted using a different linear formula.
All you need is an array of [m] and an array of [C], all the same size as your data arrray. No formula node needed.
(I think that's what mikeporter had in mind above)
Message Edited by altenbach on 07-24-2007 03:38 PM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
CorrectedArray.png ‏4 KB

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http://zone.ni.com/reference/en-XX/help/371361H-01/lvhowto/auto_indexing_1/
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dear friend
I'm trying to use formula node to solve a problem because I make this program using c at the begining.
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int32 i,j,k;
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This is the part that I think the problem might be.
if ( np[ep[i][j-1]][k] != -1 && (pc[ep[i][j-1]][ep[i][j]] + pc[ep[i][j]][exit] >= pc[ep[i][j-1]][np[ep[i][j-1]][k]] + pc[np[ep[i][j-1]][k]][exit] ) && (pc[ep[i][j-1]][np[ep[i][j-1]][k]] == org[ep[i][j-1]][np[ep[i][j-1]][k]] ))
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altenbach 已寫:
normanshi wrote:
ep[i][0] = pa[i];                                          (A)
ep[i][1] = np[ep[i][0]][0];                            (B)
...    if ( np[ep[i][j-1]][k] != -1 && ... )          (C)
      ep[i][j] = np[ep[i][j-1]][k];                       (D)
I state that "np[ep[i][j-1]][k] != -1" but I do get the value -1 in the array "ep".
Could someone tell me why I get -1 in the array?
I hope I can finally do it all by labview not using formula node,but array like "pc[ep[i][j-1]][np[ep[i][j-1]][k]] "
seems very hard to wire in labview. Could someone give me some good advices of doing this?
There are many possible scenarios to get a -1 in the ep output. For example if the -1 gets already written in step (A) or (B) at a certain index, and that index does not get overwritten in step (D). You are indexing all over the place! Is there some bounds checking on the array contents? What are typical inputs and array sizes?
I'm sure about that the -1 doesn't get already written in step (A) or (B) because ep[i][0] and ep[i][1] is fine. What really makes me confuse is that sometimes ep array has the value like this.
That means it does overwritten some value in step (D). The -1 should never be written into it because I have already state that np[ep[i][j-1]][k] != -1. Somehow I still get -1,and this is really strange! I'm indexing all over the place becuase I can't figure out a better way to achieve my requirement.
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Could you help me find out why this happened?
Thanks for your help altenbach!
由 normanshi 在 08-19-2006 10:06 PM 上編輯的訊息
Attachments:
temp4.vi ‏191 KB
ep.jpg ‏10 KB
input.jpg ‏9 KB

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