Histogram Miscount

[raging_engie]

Guys,

I am trying to write a program that will count the number and magnitude of disruptions to a load cell and record that information in a histogram.  That data is then sent to an excel report for convenience of other users.

My problem is that if you look at the attached jpeg, (the waveform chart and histogram summarize the test) you can clearly see that there are only 4 disruptions.  Can someone help me figure out why my histogram says there is 5?

Thanks

[jyang72211]

I noticed that

1. Your histogram range is 7-15 with 8 bins, but I have a peak between 6 and 7 (the first peak from left).  That peak will not be capture by the histogram. 

2. Is it possible that you have points between peaks and 5 that you are not aware of?  For example, the bin at 7, will contain all values between 7-8.  

I hope that help.

[Chris V · Accepted solution]

Hi raging_engie,

I believe that the confusion here is resulting from the way in which the histogram function works.

The histogram function does not count the number of peaks in a certain range, but the number of samples in that range.  It is a little hard to tell from your screenshot because the waveform graph is connecting samples with lines, but I believe that in one of your larger peaks, there is a sample in the 7-8 range.

Have a great day,

Chris V

[raging_engie]

But shouldnt the fact that the historgram is only recieve the maximum positive peak data from the previous express VI take care of that problem?

[jyang72211]

Put an indicator at the input of the histogram and show us exactly what is the data that you are plotting.  That should clear up confusion.  

[raging_engie]

I figured it out.  Thank you for everyone's help. It had to do with bin count but also with the the fact that the sampling rate was too fast for the buffer.