Using Waveform Chart, inconsistent results when setting X range and delta X properties

[lflash]

I have isolated my problem to a simple vi consisting of only a waveform chart (attached). I am using LV 5.1.1. I have used an attribute node to set x minimum to 0, x maximum to 10, delta x to be entered by the user, and have turned autoscaling off.

When I plot 2 random points, x maximum is inconsistent, and doesn't stay at 10 when the vi is run several times in a row. Specifically, the first time the vi is run (after delta x is changed), x maximum changes. Then, the second time it is run, the max typically goes back to 10. However, when run several times in a row, x max will fluctuate. Specifically, I tried entering a delta x of 8. Mostly, the min is 0, max is 10,
and the line between the 2 random points plots from 0 to 8 along the x axis (good). However, every once in a while, the x max will go to 8.

This behavior is very strange, and will not allow me to program my actual application correctly until I fully understand what is happening. I would assume since Waveform Chart has these attributes to set, I can still using the Waveform Chart, and don't have to completely restructure my program to use another display.

[JRA]

I have tested your VI in both LabVIEW 5.1.1 and 6.1, the most recent version. I experienced the same behavior in both situations. I would suggest contacting NI and informing them of this.

[JeanPierre]

That is the expected behavior, it is only that you don't assign the properties in the right order. If you set the XScale.Multipler before min and max all is how you expect it. When you set the multiplier, min and max are automatically changed to reflect the scale changes thus overwriting your previous settings.