Graphing two inputs

[Will9843]

Hello,

I am using the circuit displayed below to graph two voltage inputs on the same graph.  This part of the circuit works great but the graph is messy.  It appears that a line is always drawn from the the origin to one of the data points.  These are the straight lines on the graph.  How do I get rid of them?

Thank you,

William Stanford

[Mathan]

Hai william,

Your attachment was blocked and not visible. Could you please attach as a screenshot in .png format.

Thanks,

Mathan

[Will9843]

Sorry about that.  here they are:

[smercurio_fc]

I would think that you would want to use Build Array rather than Insert Into Array, and that you would want to add the new data to the end of the previous data, rather than the way you're doing it now, which is adding the new data before the old data.

[Will9843]

I added the build array in place of the insert into array but I am unsure of how to change the order in which the data is ordered and added.  What would I change to do this?

[pacific]

Hi Will9843,

To change the order, you must wire the output from your shift register to the first input of the build array function and the output of your DAQ Assistant to the second input. You also need to right click the build array function and select concatenate inputs.

[smercurio_fc]

Your questions are extremely fundamental. I would suggest spending some time learning a bit more about LabVIEW programming.

To learn more about LabVIEW it is recommended that you go through the tutorial(s) and look over the material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.

[Will9843]

I have changed the order of the inputs to the arrays and the graph still has lines going back to the origin.  When I remove the shift register controls, the graph has lines that go to the last point made in the previous run of the program.  I also tried reversing the order of the inputs on the index to array and it did not work. 

[smercurio_fc]

Have you taken a look at the actual data that you're collecting? The only way that what you're describing can happen is if you're somehow sweeping the voltage, and it's restarting at the same point. If you use a graph that uses a connected line then you will get a line going back to the start. Is this what you're doing?

[Will9843]

The voltage should not be sweeping.  The two inputs are from a linear potentiometer which reads a voltage between 0 and 5 and the other is from a pressure sensor.  The voltage from the pressure sensor is being amplified through differential amplifier.  The voltage from the pressure sensor also remains constant.  These are then inputed to the computer through an ELVIS board and displayed.