alaguerre alegendre chebs chebt chebtd chebu gegenbauer gegenbauerd gegenbauerd1 hermite jacobi jacobid jacobid1 jacobid2 laguerre legendre legendred sharmonic sharmonic_sub sharmonici sharmonicr

chebt() double chebt ( unsigned int  n, double  x  ) Chebyshev polynomial of first kind Tn(x) Purpose chebt computes the Chebyshev polynomial of the first kind Tn(x). Tn(x) = cos(nt), where x = cos(t) This polynomial follows the recurrence formula: Tn+1(x) = 2xTn(x) - Tn-1(x), where T0(x) = 1 and T1(x) = x (n > 0) Returns Chebyshev polynomial of first kind Tn(x). Parameters [in] n Argument n. (n >= 0) [in] x Argument x. Error handling Range error (ERANGE) may occur. Note If x < -1 or x > 1, this routine is much slower and recommended not to be used. Reference boost/math/special_functions