FNP1nreturns the value of the Legendre function of the first kind, degree one, and ordernofx,Pn1(x), into the real variableY.Nmust be positive or zero.
Errors
FNP1ncauses an HTBasic error if its arguments are not of the types listed in theUSAGEsection, above, ifn< 0, or if the polynomial's absolute value would be larger than MAXREAL, the largest value representable.
See Also
Pn, Q1n
Pn1(x)
Note
Forn> 12, the algorithm used computes the value ofPn1 using a recursion from the values ofP11 andP21. The computation time increases withn- 1 and the computation accuracy decreases withn- 1.