Streamlines to visualize 6-component Electromagnetic data

I am having trouble understanding and using the streamlines fucntion

I have 6-component electromagnetic data. ie. Ex,Ey,Ez & Hx,HyHz.

X = RX_Mesh;
Y = RY_Mesh;   %Km
Z = RZ_Mesh;

 startx = X(51:10:101);
 starty = Y(101:10:201);
 startz = Z(51:10:101);

freq=1

%VECTOR COMPONENTS
ex = Ex;    ey = Ey;    ez = Ez;   %electric vector components
hx = Hy_Total;    hy = Hy_Total;    hz = Hz_Total;    % magnetic vector components
u3 = Sx;    v3 = Sy;    w3 = Sz;                                     %poynting vector components

close all
streamline(X,Y,Z,ex,ey,ez,startx,starty,startz)
 hold on
 streamline(X,Y,Z,hx,hy,hz,startx,starty,startz)

using all other functions such as slice, contour, quiver3 etc my data plots as expected so it cannot be the data. I am just not understanding something correctly about the startx,starty,startz

Answer 1

[Akanksha]

Hey Sean Phillips ,

The problem with the code provided is that “startx, starty, and startz” are defined as 1D vectors, but the streamline function expects them to be 3D grids of the same size. This mismatch causes the streamlines to not generate correctly. Using "meshgrid”  function to create a proper grid of starting points would fix the issue.

Using the following code will help with your query -  
[xs, ys, zs] = meshgrid(X(51:10:101), Y(101:10:201), Z(51:10:101)); 
streamline(X, Y, Z, ex, ey, ez, xs, ys, zs); 

This will ensure that  “startx, starty, and startz” are all the same size and shape, allowing MATLAB to correctly trace streamlines from those seed points.

PFA the links for further reference:

https://www.mathworks.com/help/matlab/ref/streamline.html

https://la.mathworks.com/help/pde/ug/plots-of-gradients-and-streamlines-with-matlab-functions.html

Hope this helps!