WJcd WJcn WJcs WJdc WJdn WJds WJnc WJnd WJsc WJsd WJsn WJtheta1 WJtheta1t WJtheta2 WJtheta2t WJtheta3 WJtheta3m1 WJtheta3m1t WJtheta3t WJtheta4 WJtheta4m1 WJtheta4m1t WJtheta4t

WJdn() Function WJdn ( U As  Double, K As  Double  ) Jacobi elliptic function dn(u, k) Purpose This function computes the Jacobi elliptic function dn(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: dn(u, k) = sinφ Returns dn(u, k). Parameters [in] U Argument u. [in] K Argument k. Reference boost/math/special_functions