numeric Pi;
numeric E;

Pi := 3.14159265;
E  := 2.72828;

vardef sin(expr x) =
        sind(x/Pi*180)
enddef;

vardef cos(expr x) =
        cosd(x/Pi*180)
enddef;

vardef tan(expr x) =
        sin(x)/cos(x)
enddef;

vardef exp(expr x) =
        E**x
enddef;

vardef ch(expr x) = (E**x + E**(-x))/2 enddef;

vardef sh(expr x) = (E**x - E**(-x))/2 enddef;

vardef th(expr x) = (E**(2*x) - 1)/(E**(2*x) + 1) enddef;

endinput