Function to Draw a Circle in Matlab

MATLAB - Plotting

To plot the graph of a function, y'all need to take the following steps −

Define x, by specifying the range of values for the variable x, for which the function is to be plotted
Define the function, y = f(x)
Phone call the plot command, every bit plot(x, y)

Post-obit case would demonstrate the concept. Let us plot the simple role y = x for the range of values for x from 0 to 100, with an increment of 5.

Create a script file and type the following code −

x = [0:5:100]; y = 10; plot(ten, y)

When yous run the file, MATLAB displays the following plot −

Plotting y = x

Let u.s.a. take one more example to plot the part y = ten². In this example, nosotros volition depict 2 graphs with the same function, simply in second time, nosotros volition reduce the value of increment. Please note that equally we decrease the increase, the graph becomes smoother.

Create a script file and blazon the following code −

ten = [1 2 three 4 v half-dozen 7 8 9 ten]; x = [-100:twenty:100]; y = x.^two; plot(10, y)

When you run the file, MATLAB displays the following plot −

Plotting y = x^2

Change the code file a niggling, reduce the increase to 5 −

x = [-100:five:100]; y = x.^two; plot(10, y)

MATLAB draws a smoother graph −

Plotting y = x^2 with less increment

Calculation Title, Labels, Grid Lines and Scaling on the Graph

MATLAB allows you to add together championship, labels along the x-axis and y-axis, grid lines and also to conform the axes to bandbox upwardly the graph.

The xlabel and ylabel commands generate labels along ten-centrality and y-centrality.
The title control allows you to put a title on the graph.
The grid on command allows yous to put the grid lines on the graph.
The axis equal command allows generating the plot with the aforementioned scale factors and the spaces on both axes.
The centrality foursquare command generates a square plot.

Example

Create a script file and type the post-obit code −

x = [0:0.01:10]; y = sin(x); plot(x, y), xlabel('10'), ylabel('Sin(x)'), title('Sin(x) Graph'), grid on, centrality equal

MATLAB generates the following graph −

Sprucing up our graphs

Drawing Multiple Functions on the Aforementioned Graph

You tin can draw multiple graphs on the same plot. The following example demonstrates the concept −

Instance

Create a script file and blazon the post-obit code −

x = [0 : 0.01: 10]; y = sin(x); k = cos(10); plot(x, y, 10, g, '.-'), legend('Sin(x)', 'Cos(ten)')

MATLAB generates the following graph −

Multiple Functions on the Same Graph

Setting Colors on Graph

MATLAB provides eight basic color options for drawing graphs. The post-obit tabular array shows the colors and their codes −

Lawmaking	Color
westward	White
k	Blackness
b	Blue
r	Cerise
c	Cyan
g	Dark-green
k	Magenta
y	Yellow

Example

Let us draw the graph of ii polynomials

f(x) = 3x^four + 2x^three+ 7x^two + 2x + 9 and
g(x) = 5x³ + 9x + 2

Create a script file and blazon the post-obit lawmaking −

x = [-x : 0.01: ten]; y = 3*x.^4 + ii * x.^3 + 7 * 10.^2 + 2 * x + 9; thousand = 5 * ten.^3 + 9 * x + 2; plot(10, y, 'r', 10, g, 'g')

When you run the file, MATLAB generates the following graph −

Colors on Graph

Setting Axis Scales

The axis control allows y'all to fix the centrality scales. You can provide minimum and maximum values for x and y axes using the axis command in the post-obit way −

axis ( [xmin xmax ymin ymax] )

The post-obit example shows this −

Instance

Create a script file and type the following code −

10 = [0 : 0.01: ten]; y = exp(-x).* sin(ii*x + 3); plot(x, y), axis([0 10 -1 1])

When you run the file, MATLAB generates the following graph −

Setting Axis Scales

Generating Sub-Plots

When yous create an assortment of plots in the aforementioned figure, each of these plots is chosen a subplot. The subplot command is used for creating subplots.

Syntax for the control is −

subplot(yard, n, p)

where, chiliad and due north are the number of rows and columns of the plot assortment and p specifies where to put a particular plot.

Each plot created with the subplot command can have its own characteristics. Following case demonstrates the concept −

Example

Let united states generate two plots −

y = e^−ane.5xsin(10x)

y = eastward^−2xsin(10x)

Create a script file and type the post-obit code −

x = [0:0.01:v]; y = exp(-1.5*x).*sin(ten*x); subplot(ane,2,one) plot(x,y), xlabel('x'),ylabel('exp(–1.5x)*sin(10x)'),axis([0 5 -one ane]) y = exp(-ii*x).*sin(ten*10); subplot(ane,2,2) plot(10,y),xlabel('x'),ylabel('exp(–2x)*sin(10x)'),centrality([0 five -one 1])

When you lot run the file, MATLAB generates the following graph −

Generating Sub-Plots