Programming: keep theta between specific values

Hi every one,

I have a problem in programming. I have theta which start from 0 and goes to unspecified value. I want to reset theta if it reached to 2pi and keep it always between [0,2pi]. I wrote a code but it is not true for all situation(Ex after 4pi). My code is:

if theta>2*pi

    theta=theta-2*pi;

end

Answer 1

[Star Strider]

You can do that with the rem function:

x = linspace(0,10*pi);

theta = rem(x, 2*pi);

figure(1)
plot(x/pi,theta/pi)
grid
xlabel('Angle (x \pi)')
ylabel('Angle (x \pi)')

They are plotted as multiples of pi for convenience in visualising the result.

[Babak]

I think my explanation was not complete. I should say I get a value of theta each time not a vector. theta is a [1*1] matrix and it will increase.

[Star Strider]

A (1x1) matrix is a scalar.

My code does exactly what you illustrated. It produces vectors of values from (0,2*pi) from your linearly increasing vector that goes from zero to at least 6*pi.

Answer 2

[Babak]

I should write something like this: ( there should be an easier way!)

if 0<theta<2*pi

theta=theta-2pi;

end

if 2*pi<theta<4*pi

theta=theta-4pi;

end

if 4*pi<theta<6*pi

theta=theta-6pi;

end

[Star Strider]

Run your code and see if it produces the result you illustrated.

Mine does.