While loops and repeated reduction of a number.

I am trying to write a function file that reduces a given radian such as "7pi" until in its most basic form- between 0 and 2pi. I struggle with while loops for some reason, and this is what I have so far. So if I inputted 7pi I should get out 1pi.

>>n=r-2*pi;

>>While 0<n<2*pi

>> n=r-2*pi;

>>End

I don't know how to structure this, and I need it to work in order to implement a larger script for my project. I'm self taught, so sorry if the above is way off from accurate.

Answer 1

[Joseph Cheng]

what you are missing from your loop is the updated variable. so what you should have is something like this

Originalr = r;

While 0<r<2*pi

      r=r-2*pi;

End

your intial loop did not update so you are just performing the same subtraction over and over 7pi-2pi.

Answer 2

[Star Strider]

I suggest using the rem function:

r = (1:7)*pi;       % Example argument vector
f = rem(r, 2*pi)

produces:

f =

       3.1416     0.0000     3.1416     0.0000     3.1416     0.0000     3.1416