Wish: M_2PI QtMath

QtMath wishlist

I, for one, would welcome a new constant:

M_2PI   Two M_PI  2π

One wavelength plots of trigonometric functions, for example, Sine, Cosine, use Range(0, 2π). While creating plots of triangle and square waves with fourier series of sines and cosines in Q3DBars and QGraphicsView, each graph requires defining (M_PI * 2). It would be convenient to write qSin(M_2PI) instead of qSin(M_PI * 2).