## Archive for the 'Matlab' Category

#### Matlab: storing results from a for loop

February 13th, 2012

So I’ve been fitting exponential curves into some data points today, continuing from last week. This is when you have at least two sets of values x and y which you are guessing to be related “logistically”, so that you model this relationship by y=b*m^x. Here’s how one plot looks like:

(See MS Excel help page on LOGEST here.)

After which I want to plot these model curves using Matlab, so I am currently “copy-pasting arrays” into the Matlab command window. The job is getting a bit too much with the lot of data I have, so I think it’s time to learn coding in Matlab.

Here’s a very short but useful video tutorial that clearly shows the syntax on how to store results from a for loop into a matrix. I’m no programmer, as I’ve admitted in many a conversation to disclaim my unskilledfulness in coding.

Anyhow, if you can’t see the video, basically all you have to do is define a matrix such as mat(r,:)=y within the for loop, as shown in the example:

for r = 1: 10
y=your formula to get y involving r;
mat(r,:)=y
end

The “:” notation is very useful to refer to an entire column.