MATLAB by rudra pratap

1.6 Basics of MATLAB
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2. Figure window: The output of all graphics commanrls typed in the command
window are flushed to the graphics or figure window, a separate gray
window with (default) white background color. The user can create as many
figure windows as the system memory will allow.
3. Editor window: This is where you write, edit , create, and save your own
programs in files called M-jiles. You can use any text editor to carry out these
tasks. On most systems, MATLAB provides its own built-in editor. However,
you can use your own editor by typing the standard file-editing command that
you normally use on your system. From within MATLAB, the command is
typed at the MATLAB prompt following the exclamation character (!). The
exclamation character prompts MATLAD to return the control temporarily
to the local operating system, which executes the command following the
character. After the editing is completed, the control is returned to MATLAB.
For example, on UNIX systems, typing ! vi myprogram .m at the MATLAB
prompt (and hitting the return key at the end) invokes the vi editor on the
file myprogra m.m. Typing !emacs myprogram .m invokes Lhe emacs editor.
1.6.2 On-line help
• On-line documentation: MATLAB provides on-line help for all its builtin
functions and programming language constructs. The commands lookfor,
help, helpwin, and helpdesk provide on-line help. See Section 3.6 on page 85
for a description of the help facility.
• Demo: MATLAB has a demonstration program that shows many of iLo; features.
The program includes a tutorial introduction that is worth trying.
Type demo at the MATLAB prompt to invoke the demonstration program,
and follow the instructions on the screen.
1.6.3 Input-output
MATLAB supports interactive computation (see Chapter 3), taking the input from
the screen, and flushing the output to the screen. In addition, it can read input
files and write output files (see Section 4.3.7) . The following features hold for all
forms of input-output:
• Data type: The fundamental data type in MATLAB is an array. It encompasses
several disLlnct data objects-integers, doubles (real numbers) , matrices,
character strings, structures, and cells.3 In most cases, however, you
never have to worry about the data type or the data object declarations. For
example, there ia no need to declare variables as nml or complex. WhP.n a real
numl.Jer is euLered as the value of a variable, MATLAB automatically sets the
variable to be real (double).
3 Structures and cells as data objects were introduced in MATLAB 5. See Section 4.4 on page 121
fur their dcBcription. MATLAB also allow nPr to create their OWn data objects and MSOciatcd
operations. We do not discuss this facility in this book.