I am trying to multipy three different arrays by 3 but I do not want to simply multiply them each by three, so is there a way I can use a for or loop function to do the multiplication for me for all three arrays?
"...but I want to know if there is a basic functions to multiplty them all by three at once."
If you really want to multiply them "at once" then simply put all of the data into one numeric array (which could be a 3D array) and perform one multiplication.
If you want to keep them as separate arrays then simply store them all in one cell array (which they should be anyway) and use a basic loop:
C = {[1,2,3,4],[5,6,7,8],[9,10,11,12]};
for k = 1:numel(C)
C{k}*3
end
Defining the arrays in lots of separate variables is a mistake that will force you into writing slow, complex, inefficient, obfuscated, buggy code that is hard to debug. Indexing is much simpler and much more efficient.
You can also select a web site from the following list:
How to Get Best Site Performance
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.