query: matlab function

[nonmm]

can i use matlab function like angle, ginput into labview?

[kehander]

If you're running a recent version of LabVIEW, you can probably use some functions like that directly using a MathScript node (or even a MATLAB Script Node in some cases).

But anyway, it looks like the equivalent of the Angle function is in the Mathematics -> Numeric -> Complex palette ("Complex to Polar"); it even appears to take array input.

GInput might be a little more complicated.  You might be able to just use a cursor on an ordinary XY-graph and read its coordinates from a Property Node, depending on what your needs are.

[nonmm]

property node? how do i get this?

after i plot the graph, i click on it and it will get the data for me?

[nonmm]

how to extract data for a particular column from a .txt. let's say i got 5 columns. how to i extract just the 5th column to plot my graph. 

clear all

fid=fopen(relay.txt','r');
g=(fscanf(fid,'%f',[5,inf]))';
status=fclose(fid);

plot( g)

grid
xlabel('Time')                                
ylabel('Temperature')                               
title ('Temperature of bakeplate')

it gives me 5 plots within a graph instead of just one y values.

[kehander]

---

@nonmm wrote:

property node? how do i get this?

after i plot the graph, i click on it and it will get the data for me?

---

Right-click the graph and select Create > Property Node > Cursor > Cursor Position > All Elements.  You can then wire that property node to something else (like an indicator).

You should be able to find more information on how to manipulate graphs using property nodes on the NI website or in the LabVIEW help.

---

@nonmm wrote:

how to extract data for a particular column from a .txt. let's say i got 5 columns. how to i extract just the 5th column to plot my graph. 

clear all

fid=fopen(relay.txt','r');
g=(fscanf(fid,'%f',[5,inf]))';
status=fclose(fid);

plot( g)

grid
xlabel('Time')                                
ylabel('Temperature')                               
title ('Temperature of bakeplate')

it gives me 5 plots within a graph instead of just one y values.

---

I don't understand.  Do you want to do this in MATLAB, LabVIEW, or what?

In the example above, I think all you really need to do is replace "plot(g)" with "plot(g(:,5))".

[nonmm]

wow thanks for the plot graph. 🙂

for the property node, i try to connect to a input of the mathscript node so that i can use the x-axis i obtain from the cursor to do another calculation.

But i can't seem to connect the output of the property node to the mathscript.

why is this so?

[kehander]

If you have Context Help open (Ctrl-H), then when you move your mouse cursor over the broken wire in the Block diagram, you will see that the source is a Cluster and the sink is a Double (or 1D array of Double).  That is why that is so.

If you just want the X-coordinate, then instead of selecting the "All Elements" property in the proprerty node, you should select "Cursor X".

[nonmm]

i have tried to unbundle it. but it seems to fail. 😞

[nonmm]

i have attached the file. there is no error when i try to run. but upon running there is an error : Error 1055 occurred at Property Node (arg 1) in cursor_x.vi

[kehander]

That's probably because your graph doesn't have a cursor!  Right-click the graph, select Properties, click the Cursors tab, and then click Add.