how to refresh graph settings

[misio-pysio]

hello people,

i am having small problem with plotting measurements in real time

i have a program which takes some measurements from an instrument and want to have graphical live preview

there is main loop which goes on and on until user stops the program

within the loop, i have several frames to set and change settings

one frame is dedicated to reading from the device and plotting

my reading function (X-ed icon in the picture) returns not only data but also measurement conditions like start and stop wavelength, which i want to use to format the graph

so, i have auxiliary cluster (same as conditions) set initially to some value and each time i read data, check if conditions changed

if not, no need to refresh axes and labels (this causes flickering in my case, also dont know why),

then data is written to the graph (graph is in the same frame) 

in the case structure i set axis labels (constants) and min/max values (these are from the conditions)

in the graph, labels are displayed as they should be, but instead of proper values on the x-axis i have only number of points

anyone could explain this to me pls?

regards

[misio-pysio]

one comment: the picture is just the one simplified frame, without while loop around and some other things

also sequence locals are not correct in the picture but thats the effect of simplification for illustrative purposes

in 'false' case i simply tunnel the data and the other two wires thru the case structure

also 'cond old' are initialized in previous frame to some impossible value

as i said, my graph remembers 'wavelength' and 'power' labels, does not like start (start wavelength) and stop (stop wavelength) points

[Sarah_Coleman_NIUK]

What version of LabVIEW are you using?

[misio-pysio]

its LabView 8.0

[Sarah_Coleman_NIUK]

Hi,

I just read your post again. Could you just clarify what your requirements are? I'm assuming you want to plot your data as a function of wavelength, is that correct?

Waveform graphs plot data as a function of time, you can't directly define the data on the X Plot. To do this you need to use an XY graph.

The context help will explain how you wire this up.

If I've misunderstood your requirements please let me know.

Kind regards

Message Edited by SarahB on 02-21-2007 05:30 AM

[misio-pysio]

Sarah,

thank you for your answer

yes, i want to plot my data as a function of wavelength but updated every time i read from the instrument

i thought that i could change x-axis min and max points in waveform graph, probably i was simply wrong bout this (but still, the X axis IS formatted to the values i pass to the property nodes but after that its forced back to display number of points, so it flickers)

i shall see if XY graph behaves as i want it to behave

thx a lot for the tip!

[misio-pysio]

hello Sarah,

you were right, using XY graph instead of waveform graph has helped and fixed my problem!

thx a lot,

michal

[Sarah_Coleman_NIUK]

No problem Michal,

Glad I could help!