c++ - Radian or Degrees?

When I create matrix of rotation from Euler angles, Should I convert a degrees(Euler angles) to radians, and then count matrix of rotation for OpenGL?
But what should I do with a quaternions?
Should I do following:

void setQuaternionsFromEuler(float bank, float heading, float attitude)
{
   float DegreeToRadian = 3.14f/180.0f;
   double c1 = cos(heading/2*DegreeToRadian);
   double c2 = cos(attitude/2*DegreeToRadian);
   //...
   double s3 = sin(bank/2*DegreeToRadian);

   this.w = c1*c2*c3 - s1*s2*s3;
   //...
}

And,

void setMatrixFromEuler(float x, float y, float z)
{
   float DegreeToRadian = 3.14f/180.0f;
   x *= DegreeToRadian;
   y *= DegreeToRadian;

   //...
}

Or not?

Answer

It depends on how you define your input.

The trig functions of C++ take radian exclusively, so you need to convert to radian eventually but that may be done before the data even enters your program (such that the angle values in the resources are all in radian)