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How to determine binary file data set size

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@Ben wrote:
So too calls with an empty array could explain the difference between 44 and 52.

 

If decyphering files didn't tkae so long, I'd try to confirm with the posted data files, but my coffee is n't fully engaged yet so I will pass.

 

Ben

 


I'm not understanding you here. if you think that empty arrays could explain the difference of 8 bytes I can't follow you in this specific use case at all. The only good reason for this difference is IMHO that the complex data cluster passed into the VI does not always contain data that will generate exactly 6 floating point values for each of the 4 arrays.

 

The whole concept of creating that complex data cluster array looks questionable to me, but that is another story.

 

Just as a visual helper what I tried to explain in my previous post:

 

how a 4 * 1 array will look when streamed to disk:

 

<4> <1> <doubleval1> <doubleval2> <doubleval3> <doubleval4>

 

how a 4 * 0 array will look when streamed to disk:

 

<4> <0>

 

and a 0 * 0

 

<0> <0>

 

So the last two will both be empty arrays physically and be 2 * 4 bytes long, but they do not contain the same data.

Rolf Kalbermatter
My Blog
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Will look for empty arrays as well but when I places an indicator on the output, I never see one.

 

Just an FYI,  The reason I am needing to format the data as I am is to feed into the x-Bar R Control Chart vi from the DSC module.   It requires a 2D array to generate the control chart outputs.  And that is also why I have to save my data and pull the most recent 25 (or some number) so the control chart is created with the current data.

 

The control chart vi's create the entire chart each time as opposed to appending.  I write the data to file so I can always start each day / shift with the most redcent data displayed and continue from there, always shifting one data set over to keep the chart current. Otherwise, I would start each day and have to grow my chart and certain trends might not be seen.

 

Running with the datalogs on a short trial run today and all is good (except my Cpk)

 

Doug

Doug

"My only wish is that I am capable of learning each and every day until my last breath."
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