LabVIEW
continues process
Hi Melikan,
Right now you keep one array - the Original values. On each loop, the top array (Charted[]) is replaced with the Original array - then the last element is (possibly) modified. Maybe what you want to do is maintain two arrays - Original[] and Changed[](?) If so...
On each loop, append a value to each array. Simply append the random value to the Original array and don't modifiy if further (just wire it to shift register.) Before appending a value to Changed[], decide what value to add. You should not need to use "delete from array" and "insert into array"!
I'm very confused as to what this algorithm is accomplishing, but we can certainly simplify the code!
By the way, is this schoolwork?
Cheers!
Melikyan wrote:
For example every array start from 0,1,2,3,.....i-1,i..... numbers. In this program i need to compare 'i-1' and 'i' everytime.If abs([i-1]-[i])>0.3 [i] change to [i-1]; "i=i-1", other case continue ....i-1, i, i+1, ....). Please see this attached Vi and help me to find out my mistake...
One problem in your description is the fact that you don't distinguish between the index of an array element and the value of an array element.
If you say " [i] change to [i-1]; "i=i-1" " does that mean that you want to replace the last value without incrementing the array size OR do you just want to Not insert the new element, keeping the array size at i-1.
In other words, does the index change or does the value change (or both)?
If the values of the input array is [1, 2, 3, 3.1, 3.2, 3.3, 5, 7, 8], what should the output array be?
We cannot solve your problem unless you provide clear specifications. 🙂
Anyway, if you constantly want to compare the current element with the previous element, you should simply keep the current value in a shift register. It just complicates things in you read it out of the array at the next iteration.
Here's a quick draft that shows the idea how to arrange the shift registers. (Since I don't fully understand your problem description, the rest of the code is probably wrong, so ignore that! ;)).
Message Edited by altenbach on 06-29-2008 09:54 AM
Thanks to Pnt's post it seems this is not schoolwork - here's how I'd approach this: (with reservations Altenbach already expressed)
Comparing the newest raw value to the previous raw value seemed odd to me, so there's an option to compare the newest value to the last value actually retained in the Filtered array.
Cheers!
Message Edited by tbd on 06-29-2008 12:03 PM
OK, so you just want to substitute the previous data point for any outlier, keeping the array the same size.
Here's a quick solution for this, see if this suits your needs.
(Your code is extremely convoluted and inefficient. There is no reason to delete the undesired element and then insert a new element with the correct value. All you need is replace the value. (resizing an array (delete from array, insert into array) are both very expensive, because they force a new copy of the entire array in memory.
Message Edited by altenbach on 06-29-2008 06:52 PM
