jcd jcn jcs jdc jdn jds jelli jnc jnd jns jsc jsd jsn jtheta1 jtheta1t jtheta2 jtheta2t jtheta3 jtheta3m1 jtheta3m1t jtheta3t jtheta4 jtheta4m1 jtheta4m1t jtheta4t

jcn() double jcn ( double  u, double  k  ) Jacobi elliptic functions cn(u, k) Purpose jcn computes the Jacobi elliptic functions cn(u, k). The function is defined as follows, given: u = ∫ 1/√(1 - k^2(sin(t))^2) dt [0, φ] The angle φ is called the amplitude and: cn(u, k) = cosφ Returns cn(u, k). Parameters [in] u Argument u. [in] k Argument k. Error handling Range error (ERANGE) may occur. Reference boost/math/special_functions