* What is new in gsl-1.9:
** Fixed the elliptic integrals F,E,P,D so that they have the correct
behavior for phi > pi/2 and phi < 0. The angular argument is now
valid for all phi. Also added the complete elliptic integral
gsl_sf_ellint_Pcomp.
** Added a new BFGS minimisation method gsl_multimin_fdfminimizer_vector_bfgs2
based on the algorithm given by R.Fletcher in "Practical Methods of
Optimisation" (Second edition). This requires substantially fewer
function and gradient evaluations, and supercedes the existing BFGS
minimiser.
** The beta functions gsl_sf_beta_e(a,b) and gsl_sf_lnbeta_e(a,b) now
handle negative arguments a,b. Added new function gsl_sf_lnbeta_sgn_e
for computing magnitude and sign of negative beta values, analagous to
gsl_sf_lngamma_sgn_e.
** gsl_cheb_eval_mode now uses the same error estimate as
gsl_cheb_eval_err.
** Improved gsl_sf_legendre_sphPlm_e to avoid underflow with large
arguments.
** Added updated Knuth generator, gsl_rng_knuthran2002, from 9th
printing of "The Art of Computer Programming". Fixes various
weaknesses in the earlier version gsl_rng_knuthran. See
http://www-cs-faculty.stanford.edu/~knuth/news02.htm
** The functions gsl_multifit_fsolver_set, gsl_multifit_fdfsolver_set
and gsl_multiroot_fsolver_set, gsl_multiroot_fdfsolver_set now have a
const qualifier for the input vector x, reflecting their actual usage.
** gsl_sf_expint_E2(x) now returns the correct value 1 for x==0,
instead of NaN.
** The gsl_ran_gamma function now uses the Marsaglia-Tsang fast gamma
method of gsl_ran_gamma_mt by default.
** The matrix and vector min/max functions now always propagate any
NaNs in their input.
** Prevented NaN occuring for extreme parameters in
gsl_cdf_fdist_{P,Q}inv and gsl_cdf_beta_{P,Q}inv
** Corrected error estimates for the angular reduction functions
gsl_sf_angle_restrict_symm_err and gsl_sf_angle_restrict_pos_err.
Fixed gsl_sf_angle_restrict_pos to avoid possibility of returning
small negative values. Errors are now reported for out of range
negative arguments as well as positive. These functions now return
NaN when there would be significant loss of precision.
** Corrected an error in the higher digits of M_PI_4 (this was beyond
the limit of double precision, so double precision results are not
affected).
** gsl_root_test_delta now always returns success if two iterates are
the same, x1==x0.
** A Japanese translation of the reference manual is now available
from the GSL webpage at http://www.gnu.org/software/gsl/ thanks to
Daisuke TOMINAGA.
** Added new functions for basis splines, see the "Basis Splines"
chapter in the GSL Reference Manual for details.
** Added new functions for testing the sign of vectors and matrices,
gsl_vector_ispos, gsl_vector_isneg, gsl_matrix_ispos and
gsl_matrix_isneg.
** Fixed a bug in gsl_sf_lnpoch_e and gsl_sf_lnpoch_sgn_e which caused
the incorrect value 1.0 instead of 0.0 to be returned for x==0.
** Fixed cancellation error in gsl_sf_laguerre_n for n > 1e7 so that
larger arguments can be calculated without loss of precision.
** Improved gsl_sf_zeta_e to return exactly zero for negative even
integers, avoiding less accurate trigonometric reduction.
** Fixed a bug in gsl_sf_zetam1_int_e where 0 was returned instead of
-1 for negative even integer arguments.
** When the differential equation solver gsl_odeiv_apply encounters a
singularity it returns the step-size which caused the error code from
the user-defined function, as opposed to leaving the step-size
unchanged.
** Added support for nonsymmetric eigensystems
** Added Mathieu functions
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