Remove 0's from Graph

[Maarten91]

Hi

Im trying to plot some values that represent data recorded with 5 second intervals. The 2 plots is a mean value and a peak value. I would ideally want a line between the mean values. However in the dataset there's values that equals zero, so my graph drops to zero when this happens.

How can i remove these points from the graph?

I still want to keep the distance as if the point was still there.

Hope someone can help me out here.

/ Maarten 

[crossrulz]

You could use a FOR loop to replace all of the elements in the array that are equal to 0 with NaN.

[ben64]

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crossrulz a écrit :

You could use a FOR loop to replace all of the elements in the array that are equal to 0 with NaN.

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That will remove the zeroes but there will be no lines between the pre and post zero data (an acceptable solution in my mind if the frequency of 0 appearance is low).

Ben64

[Maarten91]

Your solution will probably not work, as theres is periods where a larger amount of the data is 0. But thanks for the response. I will see if i can find a better way to show the data.

[ben64]

You could replace a 0 with the latest previous non zero value. To have a line joining pre and post zero value you need to know the post value and there can be more than 1 consecutive 0 zero, this can get complicated to calculate the line equation and the y value of the point to replace (althought possible).

Ben64

[billko]

I guess we're assuming that the 0's are not real data?  Just checking.

[Maarten91]

Well its "data" recorded at a specific time that says: ---,-  in the .txt file.

So its not really 0, its just data that for some reason is not available at the specific time.

When i use the read from spreadsheet function in Labview the ---,- is converted to 0. 

The format in the .txt file is like this, where i'm only interessted in the last two columns:

1        ----       23.01.2002     09:06:00     70,4      94,7
2        ----       23.01.2002     09:06:05     ---,-       ---,-
3        ----       23.01.2002     09:06:10     72,3     93,1

So basically what i want is the X axis to represent the time, but not plot when no data is available.

[billko]

I like Ben64's idea, then.  🙂

It's not critical, then?  The bad data point doesn't need to be flagged as asuch?

[Maarten91]

No they don't need to be flagged, just not in included on the graph.

After some considerations i don't think i will implement a line between the data points, just show them as a dot. 

So i will go for Ben64/crossrulz solution, to replace the 0's with NaN, so they won't show up on the graph. With this i will still keep my time axis intact. 🙂

[falkpl]

Could also use an XY plot, since you have time use this real value as the x axis and data as the Y, remove time data pairs where the data is out of range (ie ==0)