cva1 Subroutine

This routine is copyrighted by Shanjie Zhang and Jianming Jin.  However, 
they give permission to incorporate this routine into a user program 
provided that the copyright is acknowledged.

25 July 2012

Shanjie Zhang, Jianming Jin

Shanjie Zhang, Jianming Jin,
Computation of Special Functions,
Wiley, 1996,
ISBN: 0-471-11963-6,
LC: QA351.C45.

Input, integer ( kind = 4 ) KD, the case code.
1, for cem(x,q)  ( m = 0,2,4,... )
2, for cem(x,q)  ( m = 1,3,5,... )
3, for sem(x,q)  ( m = 1,3,5,... )
4, for sem(x,q)  ( m = 2,4,6,... )

Input, integer ( kind = 4 ) M, the maximum order of the Mathieu functions.

Input, real ( kind = 8 ) Q, the parameter of the Mathieu functions.

Output, real ( kind = 8 ) CV(*), characteristic values.
For KD = 1, CV(1), CV(2), CV(3),..., correspond to
the characteristic values of cem for m = 0,2,4,...
For KD = 2, CV(1), CV(2), CV(3),..., correspond to
the characteristic values of cem for m = 1,3,5,...
For KD = 3, CV(1), CV(2), CV(3),..., correspond to
the characteristic values of sem for m = 1,3,5,...
For KD = 4, CV(1), CV(2), CV(3),..., correspond to
the characteristic values of sem for m = 0,2,4,...