## Setting up a MathWorks account and installing MATLAB

To participate in the Labs portion of this course, you need to set-up a MathWorks account. (Since Michigan State University has an institutional license, this should be at **absolutely no charge to you**.)
The process is fairly simple:

- First, visit the MSU-licensing page on MathWorks.
- You will click the "Sign-in to get Started" button, this button will raise the MSU log-in page, and you will need to log-in using your MSU NetID and Password. For more information concerning your NetID, please visit the MSU NetID webpage.
- This should return you to a screen asking you to associate the institutional license to a MathWorks account. If you have previously used MATLAB before, you can log-in using your existing MathWorks account. Otherwise please click on "Create a MathWorks Account" and follow the instructions there.
- Once your account is created, the MSU institutional license will be automatically applied to it.
**Make sure to remember / write down your MathWorks account information.** - With the MathWorks Account information, you should be able to log-in to MATLAB Online. You will be able to complete the Lab assignments with MATLAB Online.
- (Optional, but recommended) Once you have a MathWorks Account set up, you can download MATLAB according to the type of computer you have (Windows, Mac, or Linux). A MATLAB installation on recent (bought in the past 3 years) laptop typically runs faster than the online version; so if you have enough disk space we do recommend the installation.
- When the download completes, you can begin the installation process following the steps on MathWorks' webpage.

**Important information**: in Step 8 of MathWorks' installation guide, you are asked to "Specify Products to Install".*For this class, you only need to install the base MATLAB product*which will take approximate 1 GB of harddisk space. You can feel free to de-select all the other Toolboxes and Toolkits (the full installation can take more than 10 GB).

**Important information**: since you have already created a MathWorks account, you can use that to log-in in Step 5 of MathWorks' installation guide; in Step 7 you will want to select the MSU institutional license which should be listed in the dialog box.

## MATLAB Cheat Sheet

### Basic Syntax

#### Vectorized Arithmetic

To allow MATLAB to efficiently compute values taking advantage of vectorization, as a rule of thumb for this course we will use the period ('.') notation with the multiplication, division, and exponentiation operators.

- Addition:
`1+2`

(outputs`3`

) - Subtraction:
`3-2`

(outputs`1`

) - Multiplication:
`2 .* 3`

(outputs`6`

) - Division:
`6 ./ 2`

(outputs`3`

) - Exponentiation
`2.^3`

(outputs`8`

)

You must explicitly include the multiplication symbol between all variables. So you *cannot* write `2x`

, and must write `2 .* x`

instead.

#### Function definitions

To define a inline function, you need to specify the independent variables using the `@`

notation. To define the function $f(x) = x^3 - 2 x^2 - 3x - 5$ one would type

`f = @(x) x.^3 - 2 .* x.^2 - 3 .* x - 5`

After defining the function you can evaluate it: `f(0)`

would output the value `-5`

.

### Built-in functions

Some mathematical functions and constants are available in MATLAB.

- Trig functions:
`sin`

,`cos`

,`tan`

,`csc`

,`sec`

, and`cot`

take their usual meanings, and take radians (not degrees) as their arguments. So`tan(pi.*/4)`

will output`1`

. - The mathematical constant $\pi$ is available as
`pi`

. - Inverse trig functions:
`asin`

for inverse sine,`acos`

for inverse cosine,`atan`

for inverse tan. (If you are not familiar with with the inverse trig functions, we will learn about it in Section 6.6 of the course.) (**Caveat**: MATLAB also defines the inverse secant, cosecant, and cotangent functions`asec`

,`acsc`

, and`acot`

; the range of these functions*as defined by MATLAB*is different from what you learn in our course. So use those functions with care.) - Logarithms:
`log`

for*natural*base logarithm, which in our class we denote using $\ln$; and`log10`

for the base-10 logarithm which in our class we write as $\log$. (If you are not familiar with $\ln$ and $\log$, we will discuss them in Sections 6.2 and 6.4 of our class.) - The mathematical constant $e$ is not defined explicitly as a number, but you can access it through the natural exponential function
`exp`

. What in our class we will write as $e^x$ you can write in MATLAB as`exp(x)`

. In particular,`exp(1)`

gives the value of the constant $e$.

### Plotting commands

#### Plotting a function

If you are given a function that has been defined in MATLAB, for example `f = @(x) x.^2 + 1`

, you can plot it using the `fplot`

command: `fplot(f, [-3,4])`

would plot the function `f`

over the range $-3 \leq x \leq 4$.

If you want to superimpose two plots on the same set of axis, you can issue `hold on`

(which tells MATLAB to put subsequent graphs on the same set of axes) and `hold off`

(which tells MATLAB to put subsequent graphs on a new set of axes). So

`fplot(f, [-3,4])`

`hold on`

`fplot(g, [-3,4])`

`hold off`

`fplot(h, [-4.5])`

will produce two graphs. The first showing the plots of the functions `f`

and `g`

on the same set of axes, and the second showing only the plot of `h`

.

#### Plotting data series

To plot a list of X-values against a list of Y-values, you can use the `plot`

command.

`xvalues = [0 1 2 3 4 5 6 7]`

`yvalues = [1 5 4 2 3 6 9 0]`

`plot(xvalues, yvalues)`