How Do I Perform Variable Calculations and Write Code in MATLAB?

[atlbraves49]

I need some help with some basic MATLAB questions.

1) When writing a MATLAB code, do I create a blank new M-file, and write it there?

2) I need the program to calculate values for an equation, as I vary two variable within the equation. I'm unsure how to do this (for example, how do I define the variables, etc)

For example, say the equation is y = x^(-0.5) +z^(ln(x));

I want the program to give me values for y when i input different values for x and z. How is this accomplished?

If anyone can point me to good MATLAB tutorials that go into this kind of detail, I'd appreciate it. I've looked, including MATLABs help, and haven't found anything regarding equations and variables, etc.

Lastly, how do you comment in MATLAB?

 

[FredGarvin]

There are hundreds of web pages out there that give the basics for how to do these things in Matlab. A quick Google search will get you going.

 

[f95toli]

And the Help-files that come with Matlab are actually very good...

 

[atlbraves49]

I've looked, including MATLABs help, and haven't found anything regarding equations and variables, etc.

Can anyone provide some actual help regarding these questions?

 

[MATLABdude]

Can anyone provide some actual help regarding these questions?

Regarding this specific question, you're probably looking for an inline function:
http://en.wikibooks.org/wiki/MATLAB_Programming/Portable_Functions

That's the serial way of doing things. However, you can often perform operations on entire vectors. If you wanted to calculate, say, sin(x) between 0 and 2pi, in increments of 1/200*pi (and then plot the result), you'd do the following:

>> x=0:1/200*pi:2*pi %The colon format goes start:increment:end
>> y=sin(x) %This will generate a vector of y values for a bunch of x's
>> plot(x,y)

Additionally, perhaps start here:
http://en.wikibooks.org/wiki/MATLAB_Programming

Or here:
http://www.mathworks.com/access/helpdesk/help/techdoc/learn_matlab/bqr_2pl.html

But if you need a quick reference for a command within MATLAB, just type help COMMAND, for instance, getting help about the identity matrix creation function:
>> help eye