KKtrans_k2n(ninf,v,​k)

This function outputs real refractive indices from imaginary indices by Kramer-Kronig transformation

This function calculates the real refractive indices from input frequency v and imaginary refractive indices k. v and k are column vectors of the same length. ninf is the real refractive index at infinite frequency.
The Maclaurin method are used ,for details see K. Ohta and H. Ishida,Appl.Opt.42,952(1988).
For limited frequency range, the KK transformation results in truncation error, for details see :
M. Segal-Rosenheimer and R. Linker,J. Quant. Spectrosc. Radiat. Transfer 110, 1147(2009)