MATLAB by rudra pratap

2.3 Lesson 3: Creating an< Print in g S !_ _ _ i m p le P l o ts ---' "--- __ _ _________________ 2_5
2.3 Lesson 3: Creating and Printing Simple Plots
Goa/: To learn how to make a simple 2-D plot in MATLAB and print it out.
Time Estimates
Lesson: 10 minutes
Exercises: 40 minutes
What you are going to learn
• How to generate x- and y-coordinates of 100 equidistant points on a unit
circle.
• How to plot x vs. y and thus create the circle.
• How to set the scale of the x-axis and the y-axis to be the same, so that the
circle looks like a circle and not an ellipse.
• How to label the axes with text strings.
• How to title the graph with a text string.
• How to ;et a hard copy of the graph.
The MATI,AB commands used are
plot
axis
xlabel
ylabel
title
print
creates a 2-D line plot,
changes the aspect ratio of the x-axis and the y-axis,
annotates the x-axis,
annotates the y-axis,
puts a title on the plot, and
prints a hard copy of the plot.
This lesson teaches you the most basic graphics commands. The exercises take
you through various types of plots, overlay plots, and more involved graphics.
Method: You are going to draw a circle of unit radius. To do this, first generate
the data ( x- and y-coordinatcs of, say, 100 points on the circle), then plot the data,
and finally print the graph. For generating data, use the parametric equation of a
unit circle:
X = cos B, y = sin B, 0 ::::; e ::::; 27r.
In the sample session shown in Fig. 2.3, only the commands are listed. You
should see the output on your screen.