drawing lines on intensity graph

[hey_yo]

I want to draw lines on the intensity graph.

I already seek for some questions asked before.

I know there is a vi can draw line on the intensity graph by clicking and dragging the mouse.

But I need more precise way such as define the length and the angle between the horzontal line.

The attachment is very ideal for me. But I don't know how to use that in the intensity graph.

Is there anyone can help or give some advice?

[SmilingPhil]

I guess the function you were referring to was the "cursor"; you can enable that for the intensity graph by right clicking an intensity graph, then from the shortcut menu, select visible items > cursor legend. You would see the cursor palette appear right next to the intensity graph. Please let me know if you cannot find it. 

[Todd_Lesher]

Version 6. See if there is an intensity graph property for "PlotImages.Front". Then check for Graphics and Sound -> Picture Functions - Draw Line.vi.

[altenbach · Accepted solution]

Your example is not that great, because it uses 100% CPU on one core at all times, doing nothing.

Here is a quick rewrite of my old example here. It draws an angle with specified lenght and angle at the place where you click on the graph. This should get you started. Modify as needed. (Also remember that trigonometry is much easier when using complex numbers :D)

[hey_yo]

Dear Phil and Lesher

I am really grateful for your replying.

The reason why I didn't upload my vi is that my file is much larger than the limitation of this site.

So the cursor Phil mentioned I already used for many ways.

And I did get some(actually a lot) trouble with drawing line.vi

and Altenbach provide the example exactly I need.

I really appreciate your kind.

thank you both. ^ __ ^

And

Dear Altenbach

Your help is just like the water in the desert.

But I am studying for some exams now, I will learn your example as soon as possible.

thank you very much.   ^ __ ^

Cheers