streamtube

Create 3-D stream tube plot

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Syntax

streamtube(X,Y,Z,U,V,W,startx,starty,startz)
streamtube(U,V,W,startx,starty,startz)
streamtube(vertices,X,Y,Z,divergence)
streamtube(vertices,divergence)
streamtube(vertices,width)
streamtube(vertices)
streamtube(...,[scale n])
streamtube(ax,...)
h = streamtube(...)


Description

streamtube(X,Y,Z,U,V,W,startx,starty,startz) draws stream tubes from vector volume data U, V, W.

The arrays X, Y, and Z, which define the coordinates for U, V, and W, must be monotonic, but do not need to be uniformly spaced. X, Y, and Z must have the same number of elements, as if produced by meshgrid.

startx, starty, and startz define the starting positions of the streamlines at the center of the tubes.

The width of the tubes is proportional to the normalized divergence of the vector field.

streamtube(U,V,W,startx,starty,startz) assumes X, Y, and Z are determined by the expression

[X,Y,Z] = meshgrid(1:n,1:m,1:p)

where [m,n,p] = size(U).

streamtube(vertices,X,Y,Z,divergence) assumes precomputed streamline vertices and divergence. vertices is a cell array of streamline vertices (as produced by stream3). X, Y, Z, and divergence are 3-D arrays.

streamtube(vertices,divergence) assumes X, Y, and Z are determined by the expression

[X,Y,Z] = meshgrid(1:n,1:m,1:p)

where [m,n,p] = size(divergence).

streamtube(vertices,width) specifies the width of the tubes in the cell array of vectors, width. The size of each corresponding element of vertices and width must be equal. width can also be a scalar, specifying a single value for the width of all stream tubes.

streamtube(vertices) selects the width automatically.

streamtube(...,[scale n]) scales the width of the tubes by scale. The default is scale = 1. When the stream tubes are created, using start points or divergence, specifying scale = 0 suppresses automatic scaling. n is the number of points along the circumference of the tube. The default is n = 20.

streamtube(ax,...) plots into the axes object ax instead of into the current axes object (gca).

h = streamtube(...) returns a vector of surface objects (one per start point) used to draw the stream tubes.

Examples

Visualize flow

Use the streamtube function to indicate flow in the wind data set. The inputs include the coordinates, vector field components, and starting location for the stream tubes.

load wind
[sx,sy,sz] = meshgrid(80,20:10:50,0:5:15);
streamtube(x,y,z,u,v,w,sx,sy,sz);
view(3);
axis tight
shading interp;
camlight; 
lighting gouraud

Visualize Flow Using Vertex Data and Divergence

Use vertex data returned by the stream3 function and divergence data to visualize flow.

load wind
[sx,sy,sz] = meshgrid(80,20:10:50,0:5:15);
verts = stream3(x,y,z,u,v,w,sx,sy,sz);
div = divergence(x,y,z,u,v,w);
streamtube(verts,x,y,z,-div);
view(3);
axis tight
shading interp
camlight 
lighting gouraud

Extended Capabilities

GPU Arrays

Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

The streamtube function supports GPU array input with these usage notes and limitations:

• This function accepts GPU arrays, but does not run on a GPU.

For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Distributed Arrays

Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

Usage notes and limitations:

• This function operates on distributed arrays, but executes in the client MATLAB^®.

For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).

Version History

Introduced before R2006a