contour plotting

[junyanyap]

Hi all,

I am new to Labview.

I would like to plot the contours shown in the attached png file.

I have the program that does the sweep of VA and VC (the axises). The contour will be the power/voltage from the photodiode, produced at each VA nad VC. I am not very sure on how to do this, as I have to monitor the contours real-time.

Any help?

Thanks!

Attached are the VA and VC sweep vi and the png file.

[junyanyap]

I came upon this example on 3D contour plotting and it suits my application well. However, I can't really understand the block diagram and am unable to edit it to get the result i want.

I have attached the vi below. (Output contour plott.vi) 

There are 3 variables that i would like to have.

X-axis: VC

Y-axis: VA

Z-axis: Power Intensity

The Z-axis will be reading from an excel file that I have stored previously, whereas the x-axis and y-axis values are fixed, ranging from 0V to 20V with step of 0.01.

I am able to get the 0V to 20V with step of 0.01 using a while loop, but I would like to implement using a for loop.

The result that I would like to get will be shown in the power output.png.

Anyone can help?

[junyanyap]

I came up with the triggering sampling of DPO2024 from Tektronix.

Am not sure whether i have done it correctly.

I will be using the measured amplitude as the Z-axis in the contour plotting.

Anyone knows how to link them together?

Thanks

[junyanyap]

Anyone knows how to plot using the 3D contour? I am not sure on the array part. kind of messy.. anyone can enlighten me?

Thanks alot!

[hanrock]

To config the contour level, pick control shortcut menu->"3D Plot Properties" item->"Contour" page->"Contour" group.

To have X-Y projection, click the X-Y button on the right side of the control.

[junyanyap]

Dear hanrock,

Thanks for your reply.

I know how to wire the vi up. Just that when i run it, it doesnt get any value.

The attached vi is the updated one whereby i combined all together.

X-axis: VC (0V to 20V)

Y-axis: VA (0V to 20V)

Z-axis: Output voltage or power

I have to monitor the output real time, but I have lots of red dots in the block diagram.

Another concern is that I am using edge trigger (caused by the square waveform with duty cycle of 10%) to obtain the voltage at that particular time of trigger. I am not sure whether I used the correct method to implement this.

The array that I would like to get in the end so as to plot the 3d contour, will be something like this. So on and so for.

	VC(x-axis) value 1	VC(x-axis) value 2	...
VA(y-axis) value 1	z-axis value 1	z-axis value 3	...
VA(y-axis) value 2	z-axis value 2	z-axis value 4	...
...	...	...	...

The main flow of the program will be to conduct the voltage sweep of VA and VC and measuring the output voltage(voltage of channel 1 of oscilloscope) at each rising edge trigger caused by square waveform, then obtaining the 3D contour plot of VA, VC and Output voltage.

So far, I ran the setup on the equipments.. only the voltage sweep is working. The graph plotting and voltage waveform has no results at all.

THanks!

[junyanyap]

Sorry i did some changes.

1 more concern is that I am afraid that my timing is wrong.

In the sense that by the time the triggering starts, my voltage sweep has already begun for a certain time. How do i synchorinise both of their start time, so that i can acquisite at the correct timing as intended?

[hanrock]

	VC(x-axis) value 1	VC(x-axis) value 2	...
VA(y-axis) value 1	z-axis value 1	z-axis value 3	...
VA(y-axis) value 2	z-axis value 2	z-axis value 4	...
...	...	...	...

 

THanks!

---

You are correct about the input. But I can not run your VI because of missing drivers VIs. Can you set a probe on the PlotHelper inputs and see if the input arrays are not empty? or attach the VI with one set of inputs as contant arrays.

[junyanyap]

Hi hanrock,

I realise that my x is an empty array.

I am kind of lost now. Ain't sure why it is passing an empty array...

Cheers

[junyanyap]

I did the following changes, and the empty array error is gone. But i still dont get an output on the Voltage waveform and the 3D contour graph.

Here is the updated vi,