Hello In general when working with variables saved from the visualizer, it is helpful to use the ÔÇ£.ÔÇØ operator to find all the related parameters and attributes; when writing ÔÇ£variable+ÔÇÖ.ÔÇÖÔÇØ in the script prompt, the autocomplete feature will show these quantities in bold.
For example here you have probably used a command like:
charge = getresult("CHARGE","charge");
Jn = charge.Jn;
To define the current density matrix.
Now by starting to write ÔÇ£charge.ÔÇØ in the script prompt you will see that t (time), and x,y,z (coordinates) are other related attributes. For example try:
T = charge.t;
X = charge.x;
Using the size of these new matrices you can tell what each dimension of your original Jn matrix corresponds to.
In the case of a 2D transient simulation the three dimensions correspond to coordinates (XY), the time steps (t), and the component of the current density (x, y, or z).
Best regards

Hi Please check the number of your time steps by referring to the newly created T matrix (according to my previous response). I can't check your project but I suspect 7836 corresponds to current density values, 61 to time steps, and 3 to density component (direction).

Hi,

I had a similar question and have extracted charge.x and charge.z (I have a 2D Y-normal simulation region). Both of these have the dimensions as shown below


So for Jn I think it's like this: 133261 is the amount of nodes, 31 is the amount of voltage steps, 1 is because I only have them at one moment in time(?) and 3 because I have an x, y and z. Is this correct?
If so, how are the nodes/values structured in my X, Y or Z variable?
Best regards

Hi,
As you suggested, the X, Y, Z matrices indicate the coordinate of the mesh points (nodes). A row number corresponds to the same point for each of them so they can determine the coordinates of a reported result, here current density.
Best regards

Hi,

Thanks for quick response. So how do I know where the origin is?
And since I have just column vectors with size 133261, how do I know how many nodes there are every direction in my structure? For example say the x direction is horizontal here. If the most left node at a fixed z and y coordinate is x=0 then what is the x coordinate of the most right node?

Hi,
You would have the same number of nodes in all directions. So here you have 133261 nodes, meaning there will be 133261 coordinates for x, y, and z.
If the left most node is x = 0, the most right one will be equal to width of the simulation region in x direction. You can also use the min and max commands (and apply them to x,y, and z) to find how much your nodes span in each direction.
Best

Hi mariah
I had the same question/problem. I think that it is probably easier if your try to process the data and make your plots in Matlab or Python. I use Matlab to interpolate the data, creating a grid with in each node the interpolated value of J. Once you have this you can simply plot J versus x or z. Here's a snippet of the code I use to do this:
[xq,yq] is the grid I want to have my interpolated J values in
x and z are the vectors I obtained from Lumerical
each column of Jn_ contains the values of Jn in each node for one voltage step,
and here is the explanation of the griddata function:https://www.mathworks.com/help/matlab/ref/griddata.html

So the result of the interpolation gives you a matrix with the value of Jn in each point of the grid. If you now only want to get the current density as a function of x you just need to take only a single column/row (whichever represents the change of x values) and plot this vector against the x coordinate of your mesh grid.

And yes, you are correct, you should use 1e-6 to have the coordinates in m

Thank you for commenting this. Please let me know if you have further questions.
Best regards