Using iteration number as time on graph

[Gzimmer]

I'm making a VI that simulates the CO2 production in a room and I'd like to use the while loops iteration number as the graph's time variable (in minutes), perferably in a way that would automatically convert to DD:HH:MM.

Also, I'm trying to add cursors or lines to show thresholds but the  "show cursor legend" is grayed out, why would this be disabled?

Thank you,

Gary

[ramses64]

Hi,

what type of graph do you want to use ? A XY one ?

regards,

[Gzimmer]

Right now I'm using a Waveform Chart, but if it would be easier to use a different type I'll change.

[ramses64]

Hi,

see attached file, there are many options to build a XY graph.

You can change the display of X axis by changing options (choose for exemple relative time display)

Best regards,

[Gzimmer]

The problem with using a XY graph is that it isn't showing history data, only the current point. Also, I'm wondering if there is any way to have a reset on the time as I have in my current VI.

You can see in my VI (set it to atleast 1 occupant and >0 fan CFM) that the x-axis is useless real-time, not simulation time (where each loop step is 1 minute)

[ramses64]

Sorry, I only have labview 2009, so I cannot open yours.

With XY graph, there is no history data, you can solve this by using shift register.

[Gzimmer]

Thank you anyway, I'm currently looking at this KB article and examples.

[ramses64]

that's what i said : use shift registers and it will work.

[Gzimmer]

Ok, so since I now have the simulation minutes in the x-axis, I'd like it to be displayed as DD:HH:MM on the x-axis. The only options I can find involve using real-world time.

[Gzimmer]

Ok, I've saved for previous version what I'm working on now, with the original graph chart and implemented XY graph with history from the example subvi.