MATLAB Function Reference
streamline

Draw stream lines from 2-D or 3-D vector data

Syntax

• ```h = streamline(X,Y,Z,U,V,W,startx,starty,startz)
h = streamline(U,V,W,startx,starty,startz)
h = streamline(XYZ)
h = streamline(X,Y,U,V,startx,starty)
h = streamline(U,V,startx,starty)
h = streamline(XY)
```h = streamline(...,options)
``````

Description

`h = streamline(X,Y,Z,U,V,W,startx,starty,startz)` draws stream lines from 3-D vector data `U`, `V`, `W`. The arrays `X`, `Y`, `Z` define the coordinates for `U`, `V`, `W` and must be monotonic and 3-D plaid (such as the data produced by `meshgrid`). `startx`, `starty`, `startz` define the starting positions of the stream lines. The section Starting Points for Stream Plots in Visualization Techniques provides more information on defining starting points.

The output argument `h` contains a vector of line handles, one handle for each stream line.

`h = streamline(U,V,W,startx,starty,startz)` assumes the arrays `X`, `Y`, and `Z` are defined as `[X,Y,Z] = meshgrid(1:N,1:M,1:P)` where `[M,N,P] = size(U)`.

`h = streamline(XYZ)` assumes `XYZ` is a precomputed cell array of vertex arrays (as produced by `stream3`).

`h = streamline(X,Y,U,V,startx,starty)` draws stream lines from 2-D vector data `U`, `V`. The arrays `X`, `Y` define the coordinates for `U`, `V` and must be monotonic and 2-D plaid (such as the data produced by `meshgrid`). `startx` and `starty` define the starting positions of the stream lines. The output argument `h` contains a vector of line handles, one handle for each stream line.

`h = streamline(U,V,startx,starty)` assumes the arrays `X` and `Y` are defined as `[X,Y] = meshgrid(1:N,1:M)` where `[M,N] = size(U)`.

`h = streamline(XY)` assumes `XY` is a precomputed cell array of vertex arrays (as produced by `stream2`).

`streamline(...,options)` specifies the options used when creating the stream lines. Define `options` as a one or two element vector containing the step size or the step size and the maximum number of vertices in a stream line:

• ```[stepsize]
```

or

• ```[stepsize, max_number_vertices]
```

If you do not specify values, MATLAB uses the default:

• stepsize = 0.1 (one tenth of a cell)
• maximum number of vertices = 1000

Examples

This example draws stream lines from data representing air currents over a region of North America. Loading the `wind` data set creates the variables `x`, `y`, `z`, `u`, `v`, and `w` in the MATLAB workspace.

The plane of stream lines indicates the flow of air from the west to the east (the x direction) beginning at x = 80 (which is close to the minimum value of the x coordinates). The y and z coordinate starting points are multivalued and approximately span the range of these coordinates. `meshgrid` generates the starting positions of the stream lines.

• ```load wind
[sx,sy,sz] = meshgrid(80,20:10:50,0:5:15);
h = streamline(x,y,z,u,v,w,sx,sy,sz);
set(h,`'`Color`'`,`'`red`'`)
view(3)
```

See Also

`coneplot`, `stream2`, `stream3`, `streamparticles`

Volume Visualization for related functions

Specifying Starting Points for Stream Plots for related information

Stream Line Plots of Vecotr Data for another example

 stream3 streamparticles