Plot error bars

[Greg Vowles]

I have found the NI webpage "Plotting Error Bars in LabVIEW ("Stick Plots") which gives an example of how to plot the Y error bars.  This example works fine for plotting the Y errors and I have modified it so that it will also plot the x errors as well (see attached gif-picA). 

Because an error bar is just a single graph with X(or Y) constant, when I plot the data with the error bars the error bars are each plotted to be different colors.  While this looks pretty, I need to have all the error bars to be the same color.  To fix this I progmatically change each plots color using a property node (see atteched gif-picB).  This seems to work for small data sets but the problem is if I have a lot of data points it takes several minutes to change all the error plots colors.  I need a quicker/better solution.  It is possibble that I could have data sets as big as 10000 or more.

Does anyone have any suggests/ideas that I could try to speed this up?  Is there a better way of plotting error bars? 

Thanks!

G

ref:

http://zone.ni.com/devzone/cda/epd/p/id/1404

[unclebump]

Try the Min Max plot, but you have to reshape your data.

[Greg Vowles]

Hi unclebump,

Thanks for the reply. 
I took a look at the Min Max plot example that you suggested but it doesn't quite help with the X error bars.  Also try changing the constant for the number of iterations on the first for loop from100 to 10000 - It caused LabVIEW to crash with a "not enough memory error". 

The problem is that the errorbar.vi creates stick plots for each data point so for a data set of 10000 points it creates 30000 individual plots (10000 for data points, 10000 for Y error bars and 10000 for the x error bars). 

Any other suggestions?

[unclebump]

Sounds like a case for an activex excel line chart with error bars added to it.

[ttrr]

Hi,

If you use LabVIEW 8.20, you can find function errorbar in MathScript. Try it!

[unclebump]

I found this on LAVA.

also these.

http://zone.ni.com/devzone/cda/tut/p/id/3190

http://zone.ni.com/reference/en-XX/help/371361B-01/lvtextmath/msfunc_errorbar/

http://ssf.ugent.be/linac/linac/graph_with_error_bars.htm

[Greg Vowles]

Thanks unclebump,

The XYGraphErrorBars example that you provided was exactly what I was looking for.

Thanks again for your quick responses!

G