If you are trying to assign a value to a particular element in a matrix, do not use a for loop. Suppose you have a 5x5 matrix called A. If you want to set the 3rd row, 2nd column to be 1, simply do "A(3,2) = 1;". Do NOT do:

		       % Note: this is an example of what NOT to do.
                       for i=3
		           A(i,2) = 1;
		       end
		       

Also, to access or look at the value of an element of an array called A... If you want to look at row r, column c, then use "A(r,c)". For example, to test if the element at row r, column c is a 1, you can do:

                       if (A(r,c) == 1)
		          % then do something
		       end
		       

Do not name your functions with names that you think MatLab might already be using for something. For example, do not call your function any of the following: factor, network, square, poly, ... If you can think of a reason MatLab would have a function with a certain name already, then it probably does. You can find out if there is already a function defined with a certain name by trying to look it up in the help. If you do accidentally name your function after something that MatLab has already defined, some weird things can happen.

Also, make sure to save your .m file as the same name of your function. If you don't, then it won't work.

Check out the "Additional Exercises" column for the second week of Matlab on the syllabus for extra examples. Make sure you can explain why the examples behave as they do.

Now that you've gotten used to "Pi" in Maple, be careful when switching to Matlab.

Scripts are just a series of commands (which you could have entered one by one in the command window) saved in a file, so that you can run them all with just a single command in the command window. Putting commands in scripts makes debugging and changing code easier. Scripts can see any variables currently in the workspace, and may modify them inside the script.
Functions are also a series of commands, but they take one or more input arguments, and return one or more values. To call a function in the command window, unlike a script you must pass it values for the arguments it expects. If you want a function to know about a variable in your workspace, you must pass it to the function explicity. Functions cannot modify the variables in your workspace.

The name of the parameters which you pass a function do not need to be the same as the name you give the arguments in the function. e.g. If the function f(x) is declared as "function y = f(x)" in an m-file, then in the command window I can call it as: "f(a)" or "f(b)" etc. (assuming that the variables "a" and "b" have been declared in my workspace).

Use comments to explain what your code is doing. Don't just repeat the code line for line in English, but outline the general purpose of sections or particularily tricky lines. A bit of code explaining each for loop and/or if statement can be a good general rule. Make sure that if you come back to the code in a few weeks (e.g. before a test), you'll be able to understand what it is doing.
A good strategy is to first lay out in comments what you want to do (this is called "pseudocode"), and then go back and fill in the actual code for each step once you've outlined the whole approach.

To assign a value to a variable, use a single equals sign. e.g. "x = [1:4];" To test if a variable has a certain value, or two variables have the same value, use two equals sign. e.g. "if x == 4"

These matlab commands take a function name in single quotes as their first argument. Notice, it's the name of the function, not the name of the file that the function is in, so there's no ".m". Also, it's just the name - you don't supply any input arguments, or put any parentheses. For instance, if you have a function "ToBeZero", you would write: fzero('ToBeZero', 2.718). You can NOT write: fzero('ToBeZero-20', 2.718) or fzero('ToBeZero(x)', 2.718).
This is the only time you'll use function names in single quotes, the rest of the time you'll want to call the function like normal, i.e. ToBeZero(x).