09-28-2011 04:51 PM
Hello,
Im using the Express VI to build XY graph. Im acquiring signals from multiple channels and i should plot the waveforms for different channels as the test is running. Im having problems clearing the history. Looking at the other posts and previous threads, i did create a property node "Value" and created a constant array input to the "Value". I also created the "Reinit default value" node. Im still seeing the data from the previous channel.
The same trick worked well when i used waveform chart, but i will need to do the same with XY graph.
I have attached the VI, the "Index" lets you switch form one channel to the other, if i change the "Index" value, the waveform does show the value of the corresponding channel, but, it contains the data of the previous channel.
For instance, if i change the "Index" from 0 to 1 after 10 secs, it still shows the value of "Index" 0 from 1second to 10 seconds. But i would like to see the value of "Index" 1 for the same time period and continue showing values of "Index" 1 until changed by the user.
The second attachment is a sub-VI.
Thank you,
Eureka
09-29-2011 05:47 PM
One of the main differences between the Chart and Graph is that the Graph does not have a history. Because of this there is no need to "clear" it. It redraws whenever you send new data to it. I would recomend checking the program logic using the highlight execution and watching to see when your array index changes and rewrites the graph vs. when you as a user change "index".
Kyle K.