Created Saturday 15 August 2020
Trigonometric function definitions in degrees:
TRIG='define pi() { return (a(1)*4) }
define torad(a) { return a*pi()/180 }
define todeg(x) { return x*180/pi() }
define sin(a) { return s(torad(a)) }
define cos(a) { return c(torad(a)) }
define tan(a) { return sin(a)/cos(a) }
define asin(x) { if(x==1) { z=90 } else { z=todeg(a(x/(sqrt(1-x^2)))) }; return z }
define acos(x) { return asin(sqrt(1-x^2)) } define atan(x) { return todeg(a(x)) }'
echo $TRIG'atan(1)' | bc -l