Constants

The following constants are available:

Constant	Value	Comment
gammalib::pi	$\pi$
gammalib::twopi	$2\pi$
gammalib::fourpi	$4\pi$
gammalib::pihalf	$\pi /2$
gammalib::inv_pihalf	$(\pi /2{)}^{-1}$
gammalib::inv_sqrt2pi	$(\sqrt{2\pi }{)}^{-1}$
gammalib::inv_sqrt4pi	$(\sqrt{4\pi }{)}^{-1}$
gammalib::pi2	${\pi }^2$
gammalib::deg2rad	$\pi /180$	Multiplication converts degrees to radians
gammalib::rad2deg	$180/\pi$	Multiplication converts radians to degrees
gammalib::ln2	$\log 2$	Natural logarithm of 2
gammalib::ln10	$\log 10$	Natural logarithm of 10
gammalib::inv_ln2	$(\log 2{)}^{-1}$
gammalib::inv_ln10	$(\log 10{)}^{-1}$
gammalib::inv_loge	$({\log }_{10}(\exp 1){)}^{-1}$
gammalib::onethird	$1/3$
gammalib::twothird	$2/3$
gammalib::fourthird	$4/3$
gammalib::sqrt_onehalf	$\sqrt{1/2}$
gammalib::sqrt_pihalf	$\sqrt{\pi /2}$
gammalib::sqrt_two	$\sqrt{2}$;
gammalib::sqrt_twopi	$\sqrt{2\pi }$