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