comet

2-D comet plot

Syntax

comet(y)

comet(x,y)

comet(x,y,p)

comet(ax,x,y,p)

Description

comet(y) displays a comet plot of the data specified in y versus the index of each value. A comet is an animation of a marker (head) and a line (tail) tracing a growing line over the data points. The tail is a solid line that traces the entire function.

comet(x,y) displays a comet plot of y versus x.

comet(x,y,p) specifies the comet body length. The comet body is a trailing segment in a different color that follows the head before fading. The body length is p*length(y), where p is a scalar in [0, 1).

comet(ax,x,y,p) plots the comet into the axes specified by ax.

Examples

Create Comet Plot

Create a comet plot of data in y versus data in x. Create y as a vector of sine function values for input values between 0 and $2\pi$. Create x as a vector of cosine function values for input values between 0 and $2\pi$. Use an increment of $\pi /100$ between the values. Then, plot the data.

t = 0:pi/100:2*pi;
y = sin(t);
x = cos(t);
comet(x,y)

Control Comet Body Length

Create a comet plot and specify the comet body length by setting the scale factor input p. The comet body is a trailing segment in a different color that follows the head before fading.

Create x and y as vectors of trigonometric functions with input values from 0 to $4\pi$. Specify p as 0.5 so that the comet body length is 0.5*length(y). Then, plot the data.

t = 0:pi/50:4*pi;
x = -sin(t) - sin(t/2);
y = -cos(t) + cos(t/2);
p = 0.5;
comet(x,y,p)

Create Plots in Specified Axes

Create two comet plots in a tiled chart layout by specifying the target axes for each plot. Create two data sets, x1 and y1 and x2 and y2 as vectors of trigonometric functions with input values from 0 to $4\pi$. Specify the body length scale factor p as 0.25 so that the body length is 0.25*length(y).

t = 0:pi/20:4*pi;
x1 = -cos(t) + cos(t/2);
y1 = -sin(t) - sin(t/2);
x2 =  cos(t) - cos(t/2);
y2 = -sin(t) - sin(t/2);
p = 0.25;

Store the two Axes objects as ax1 and ax2. Specify the target axes for each comet plot by including the Axes object as the first input argument to comet.

tiledlayout(1,2);
ax1 = nexttile;
ax2 = nexttile;

comet(ax1,x1,y1,p)
comet(ax2,x2,y2,p)

Input Arguments

y — y-values

vector

y-values, specified as a scalar or vector. To plot against specific x-values you must also specify x. If you specify geographic axes for ax, then y represents longitude in degrees.

x — x-values

vector

x-values, specified as a vector. x and y must be the same length. If you specify geographic axes for ax, then x represents latitude in degrees.

p — Comet body length scale factor

0.1 (default) | scalar in [0, 1)

Comet body length scale factor, specified as a value in the interval [0, 1). The comet body length is p*length(y).

ax — Target Axes

Axes object | GeographicAxes object

Target axes, specified as an Axes object or GeographicAxes object.

Limitations

• Comet plots do not support data tips.

Extended Capabilities

GPU Arrays

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

The comet 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