streamparticles
Plot stream particles
Syntax
streamparticles(vertices)
streamparticles(vertices,n)
streamparticles(...,'PropertyName',PropertyValue,...)
streamparticles(ax,...)
streamparticles(line_handle,...)
h = streamparticles(...)
Description
streamparticles(vertices)
draws stream particles of a vector field. Stream particles are usually
represented by markers and can show the position and velocity of a
streamline. vertices is a cell array of 2-D or
3-D vertices (as if produced by stream2 or stream3).
streamparticles(vertices,n)
uses n to determine how many stream particles to
draw. The ParticleAlignment property controls how n is
interpreted.
If
ParticleAlignmentis set tooff(the default) andnis greater than1, approximatelynparticles are drawn evenly spaced over the streamline vertices.If
nis less than or equal to1,nis interpreted as a fraction of the original stream vertices; for example, ifnis0.2, approximately 20% of the vertices are used.ndetermines the upper bound for the number of particles drawn. The actual number of particles can deviate fromnby as much as a factor of 2.If
ParticleAlignmentison,ndetermines the number of particles on the streamline having the most vertices and sets the spacing on the other streamlines to this value. The default value isn = 1.
streamparticles(...,'
controls the stream particles using named properties and specified
values. Any unspecified properties have default values. MATLAB® ignores
the case of property names.PropertyName',PropertyValue,...)
streamparticles(ax,...) creates the stream
particles in the axes specified by ax instead of
in the current axes (gca). The option ax can
precede any of the input argument combinations in the previous syntaxes.
Stream Particle Properties
Animate — Stream particle motion [nonnegative
integer]
The number of times to animate the stream particles. The default is 0,
which does not animate. Inf animates until you enter Ctrl+C.
FrameRate — Animation frames per second
[nonnegative integer]
This property specifies the number of frames per second for the animation.
Inf, the default, draws the animation as fast as possible.
Note that the speed of the animation might be limited by the speed of the computer.
In such cases, the value of FrameRate cannot necessarily be
achieved.
ParticleAlignment — Align particles
with streamlines [ on | {off} ]
Set this property to on to draw particles
at the beginning of each streamline. This property controls how streamparticles interprets
the argument n (number of stream particles).
Stream particles are primitive line objects. In addition to
stream particle properties, you can specify any line property, such
as Marker. streamparticles sets
the following line properties when called.
Line Property | Value Set by streamparticles |
|---|---|
LineStyle | 'none' |
Marker | 'o' |
MarkerEdgeColor | 'none' |
MarkerFaceColor | 'red' |
You can override any of these properties by specifying a property
name and value as arguments to streamparticles.
For example, this statement uses RGB values to set the MarkerFaceColor to
medium gray:
streamparticles(vertices,'MarkerFaceColor',[.5 .5 .5])
streamparticles(line_handle,...)
uses the line object identified by line_handle to
draw the stream particles.
h = streamparticles(...)
returns a vector of handles to the primitive line objects it creates.
For a list of properties, see Line Properties.
Examples
Animate Flow Without Displaying Streamlines
This example uses streamlines in the z = 5 plane to animate the flow along these lines with stream particles.
load wind figure daspect([1,1,1]); view(2) [verts,averts] = streamslice(x,y,z,u,v,w,[],[],5); sl = streamline([verts averts]); axis tight manual off; set(sl,'Visible','off') iverts = interpstreamspeed(x,y,z,u,v,w,verts,.05); zlim([4.9,5.1]); streamparticles(iverts, 200, ... 'Animate',15,'FrameRate',40, ... 'MarkerSize',10,'MarkerFaceColor',[0 .5 0])
