Getting started with MATLAB or Python

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Introduction to the Command Line

MATLAB

  • MATLAB IS CASE SENSITIVE!!! For example, A is not the same thing as a. This is very important when working with variable and function names.

Common Command Line Commands and Functions

doc function_name

Brings up information on any built-in MATLAB function (i.e. it accesses the help directory entry).

Before After
MATLAB doc before.PNG
MATLAB doc after.PNG
edit

Opens the text editor

Before After
MATLAB edit before.PNG
MATLAB edit after.PNG


clc

Clears the screen

Before After
MATLAB clc before.PNG
MATLAB clc after.PNG


clear

Clears the variables from the workspace (and from memory)

Before After
MATLAB clear before.PNG
MATLAB clear after.PNG


Built in Functions

MATLAB has an array of simple built in functions. Basically all of the rudimentary calculation types that you can think of (sin,cos,exp,etc.) have a built in MATLAB function that may be called at the command line and coded into a script or function file (as the need arises). A few examples are shown in the screenshot below.

MATLAB Common Functions.PNG


Built in Constants

MATLAB also has predefined variables for fundamental constants (ex. pi, Inf, i). Be wary though, as these can be easily overwritten by the user. As a rule of thumb try not to name your variables after any fundamental mathematical constant.

MATLAB constants.PNG


fprintf() and disp()

fprintf() and disp() provide a means of printing text to the command window. While obviously not useful at the command line (as the example below shows), these statements will become useful when you begin writing your own scripts and functions (either as a means of displaying intermediate results or as a means of tracking down bugs). disp() is a simple display function that prints arrays or strings directly to the command window. fprintf() is a more robust function that allows formatting of the string to be printed as well as output specification (for use in printing to files). The default output is set to the command window.

MATLAB fprintf.PNG
Semicolon

Placing a semicolon at the end of a line of code will suppress any output produced by that line. This (along with fprintf() and break points) can help in debugging code. Unless you are debugging it is good practice to end all lines of code with a semi-colon to avoid a bunch of garbage intermediate values being printed out at the command line.

MATLAB semi colon.PNG
Variables
MATLAB variables.PNG
Matrices
MATLAB Matrices.PNG
Matrix Operations
MATLAB matrix operations.PNG
Dot and Colon Operator
MATLAB dot colon.PNG
Accessing Submatrices
MATLAB sub matrices.PNG
Concatenation
MATLAB concatenation.PNG



Python


Scripts and Functions

MATLAB


Python


Code Structures

MATLAB


Python


Plotting Data

MATLAB


Python


Additional Resources

MATLAB


Python