converge values to range [-pi,pi] in matlab, NOT using wraptopi

Question

The assignment is: Reset the values stored in the matrix accordingly, so that they lie within this range [-pi,pi]. Take care not to use any non-standard Matlab function(s) to do this.

(of course are all angles theta + 2n*pi the same, for any integer n. Therefore for example: an angle of 1.5*pi should be reset to -0.5*pi.)

The nonstandard matlabfunction wraptopi does this (I think), but I am not allowed to use this function. I've got the feeling that I could use modulo to do this, but I don't know how.

Could anyone help me please?

Thanks in advance

Answer 1

To expand on @Ben Voight, you could use modulo-style operations this way:

To wrap to [0, 2*pi], you'd do this:

angle_rad = angle_rad - 2*pi*floor(angle_rad/(2*pi));

To wrap to [-pi, +pi], you'd add another term

angle_rad = angle_rad - 2*pi*floor( (angle_rad+pi)/(2*pi) );