changelog

math library from gnu

2008-12-04  Brian Gough  <[e-mail]>

	* gamma_inc.c (gamma_inc_D): propagate cancellation error
	in (x-a)/x for x close to a

2008-12-03  Brian Gough  <[e-mail]>

	* exp.c (exprel_n_CF): changed N to double, to allow non-integer
	usage for gamma_inc, double error factor to allow for two
	parameters in recurrence.
	(gsl_sf_exprel_n_CF_e): exported function to allow calls to
	exprel_n_CF

	* gamma_inc.c (gamma_inc_P_series): improved convergence condition
	using estimate of the remainder of the series, added continued
	fraction as a fallback, increased nmax to 10000

2008-08-26  Brian Gough  <[e-mail]>

	* ellint.c (gsl_sf_ellint_Kcomp_e): corrected taylor expansion for
	k close to 1.

2008-07-03  Brian Gough  <[e-mail]>

	* Makefile.am (INCLUDES): use top_srcdir instead of top_builddir

2008-06-27  Brian Gough  <[e-mail]>

	* legendre_poly.c (gsl_sf_legendre_array_size): removed inline
	version of this function in gsl_sf_legendre.h

2008-03-17  Brian Gough  <[e-mail]>

	* hyperg_2F1.c (gsl_sf_hyperg_2F1_e): replace duplicate error
	check on stat3 by stat4

2008-03-15  Brian Gough  <[e-mail]>

	* bessel.c (gsl_sf_bessel_Jnu_asympx_e): use full asymptotic
	series

2008-03-14  Brian Gough  <[e-mail]>

	* bessel_j.c (gsl_sf_bessel_jl_e): increase error estimate by
	factor of 2

2008-02-09  Brian Gough  <[e-mail]>

	* exp.c (gsl_sf_exp_e10_e): only use exponent e10 when standard
	exp() is out of range
	(gsl_sf_exp_mult_e10_e): add full set of error terms

2008-01-10  Brian Gough  <[e-mail]>

	* hyperg_2F1.c (gsl_sf_hyperg_2F1_e): handle case of x==1

2007-10-25  Brian Gough  <[e-mail]>

	* bessel.c (gsl_sf_bessel_J_CF1): handle underflow by rescaling in
	recurrence

2007-09-13  Brian Gough  <[e-mail]>

	* ellint.c (gsl_sf_ellint_Pcomp_e): remove test for n <1, no
	restriction needed

2007-09-10  Brian Gough  <[e-mail]>

	* expint.c (gsl_sf_expint_En_e): added for support En(x)
	(gsl_sf_expint_En_scaled_e): added for support En(x) scaled

	* gamma_inc.c (gamma_inc_CF): include finite precision of log term

2007-08-30  Brian Gough  <[e-mail]>

	* psi.c (psi_complex_rhp): accumulate error, to allow for
	cancellation effects

	* beta.c (gsl_sf_lnbeta_sgn_e): added missing factor of 2 for
	error.

2007-08-27  Brian Gough  <[e-mail]>

	* beta_inc.c (gsl_sf_beta_inc_e): handle cases where a<=0 or b<=0

2007-04-27  Brian Gough  <[e-mail]>

	* lambert.c (halley_iteration): increase tolerance to prevent
	exceeding max iters due to finite precision

2007-04-04  Brian Gough  <[e-mail]>

	* laguerre.c (gsl_sf_laguerre_n_e): use recursion for a=0 in
	addition to a>0
	
2007-02-17  Brian Gough  <[e-mail]>

	* log.c (gsl_sf_log_e): removed HIDE_INLINE_STATIC

	* exp.c (gsl_sf_exp_e): removed HIDE_INLINE_STATIC

2007-02-14  Brian Gough  <[e-mail]>

	* mathieu_charv.c: made solve_cubic static

2007-02-12  Brian Gough  <[e-mail]>

	* mathieu_charv.c (figi): ensure that e[ii] is set when
	e2[ii]==0.0 and there is no error condition, as per the original
	eispack routine

2007-02-09  Brian Gough  <[e-mail]>

	* ellint.c (gsl_sf_ellint_F_e): do argument reduction for phi>pi/2
	(gsl_sf_ellint_E_e): do argument reduction for phi>pi/2
	(gsl_sf_ellint_P_e): do argument reduction for phi>pi/2
	(gsl_sf_ellint_D_e): do argument reduction for phi>pi/2
	(gsl_sf_ellint_Dcomp_e): added complete D integral
	(gsl_sf_ellint_Pcomp_e): added complete P integral

2007-01-31  Brian Gough  <[e-mail]>

	* beta.c (gsl_sf_lnbeta_sgn_e): added to support calculations with
	negative a,b
	(gsl_sf_lnbeta_e): rewritten in terms of gsl_sf_lnbeta_sgn_e
	(gsl_sf_beta_e): handle negative a,b

	* gamma.c (gsl_sf_lngamma_sgn_e): make error calculations an exact
	copy of gsl_sf_lngamma_e (these functions could be merged to avoid
	duplication)

2007-01-29  Brian Gough  <[e-mail]>

	* test_legendre.c (test_legendre): added extra test cases for
	underflow

2007-01-26  Brian Gough  <[e-mail]>

	* expint.c (expint_E2_impl): handle x==0.0 as a special case
	(expint_E2_impl): corrected error term

	* gsl_sf_log.h: removed inline version of log

	* gsl_sf_exp.h: removed inline version of exp

2007-01-23  Brian Gough  <[e-mail]>

	* hyperg_1F1.c (hyperg_1F1_1_series): increase accuracy by factor
	of 4 in sum, tighter convergence condition, increase error
	estimate to allow for accumulated roundoff
	(hyperg_1F1_1): use series when |x| > |b|
	(gsl_sf_hyperg_1F1_e): only use Kummer when |x| < 100 otherwise
	exponential takes extreme value

	* hyperg.c (gsl_sf_hyperg_1F1_series_e): allow 10000 iterations in
	series to extend valid range
	(gsl_sf_hyperg_1F1_series_e): increase accuracy by factor of 4 in
	sum, tighter convergence condition

2007-01-19  Brian Gough  <[e-mail]>

	* laguerre.c (laguerre_large_n): use the second term in the
	asymptotic expansion from Slater, p.73.

2007-01-17  Brian Gough  <[e-mail]>

	* hyperg_1F1.c (hyperg_1F1_largebx): asymptotic expansion for
	large b and x, with |x|<|b| from Slater 4.3.7
	(hyperg_1F1_1): use new asymptotic expansion for |x|<|b|
	(hyperg_1F1_small_a_bgt0): use new asymptotic expansion for |x|<|b|
	(hyperg_1F1_renorm_b0): add neglected terms in expansion for AS13.3.7

2007-01-14  Brian Gough  <[e-mail]>

	* legendre_poly.c (gsl_sf_legendre_sphPlm_e): added explicit
	computation of error term to allow for case when final term is
	zero.

2007-01-12  Brian Gough  <[e-mail]>

	* trig.c (gsl_sf_angle_restrict_symm_err_e): compute edge cases
	more reliably, return NaN when total loss of precision
	(gsl_sf_angle_restrict_pos_err_e): as above

	* legendre_poly.c (gsl_sf_legendre_Pl_e): improve error estimate
	for large l by including rounding error at each step of recurrence

2006-10-03  Brian Gough  <[e-mail]>

	* poch.c (gsl_sf_lnpoch_e, gsl_sf_lnpoch_sgn_e): corrected
	result->val to 0.0 for x==0, previously returned incorrect value
	1.0

2006-09-24  Brian Gough  <[e-mail]>

	* laguerre.c (laguerre_large_n): work with small angles to avoid
	cancellation error, computer angular reduction exactly for integer
	eta.

2006-09-22  Brian Gough  <[e-mail]>

	* zeta.c (gsl_sf_zeta_e): make sin_term exactly zero for negative
	even integers
	(gsl_sf_zetam1_int_e): return value is -1 for zetam1_int with
	negative even integers

2006-03-26  Brian Gough  <[e-mail]>

	* fermi_dirac.c (fd_neg): initialize s to zero (avoid spurious
	warning from compiler)

2006-02-23  Brian Gough  <[e-mail]>

	* coulomb.c (gsl_sf_coulomb_wave_FG_e): fixed sign of F_lam_min,
	covers case when k_lam_G is nonzero and F_lam_min and F_lam differ
	in sign.

2006-01-21  Brian Gough  <[e-mail]>

	* synchrotron.c (gsl_sf_synchrotron_1_e): added first order
	correction term for the taylor expansion
	(gsl_sf_synchrotron_2_e): added first order correction term for
	the taylor expansion

2006-01-20  Brian Gough  <[e-mail]>

	* bessel_j.c (gsl_sf_bessel_jl_e): limit the use of
	gsl_sf_bessel_Jnu_asympx_e to the range x>100*l*l to satisfy
	the requirement x>>l*l in the asymptotic expansion

	* bessel_In.c (gsl_sf_bessel_In_scaled_e): limit the use of
	gsl_sf_bessel_I_CF1_ser to the region where the continued
	converges with the allowed 20000 terms (|x|<1e7)

2005-12-20  Brian Gough  <[e-mail]>

	* debye.c (gsl_sf_debye_5_e, gsl_sf_debye_6_e): added n=5,6
	(R. J. Mathar)

2005-11-15  Brian Gough  <[e-mail]>

	* dilog.c (dilog_xge0): fix calculation of error estimate

2005-08-04  Brian Gough  <[e-mail]>

	* coulomb.c (gsl_sf_coulomb_wave_sphF_array): fix warning about
	variable shadowing for k

2005-07-29  Brian Gough  <[e-mail]>

	* gamma_inc.c (gsl_sf_gamma_inc_Q_e): use continued fraction close
	to peak of the integrand x > a - sqrt(a)

2005-07-28  Brian Gough  <[e-mail]>

	* elljac.c (gsl_sf_elljac_e): use separate iterations to avoid
	division by zero, new algorithm from Bulirsch avoids inverse trig
	functions.

2005-07-03  Brian Gough  <[e-mail]>

	* legendre_poly.c (gsl_sf_legendre_sphPlm_e): compute exponential
	internally to avoid underflow error when calling gsl_sf_exp_err

2005-07-02  Brian Gough  <[e-mail]>

	* bessel_i.c (gsl_sf_bessel_il_scaled_array): handle x==0 as a
	special case

	* bessel_k.c (gsl_sf_bessel_kl_scaled_array): added lmax==0 as a
	special case

	* bessel_y.c (gsl_sf_bessel_yl_array): added lmax==0 as a special
	case

	* transport.c (gsl_sf_transport_2_e): improve error estimate for
	small x

2005-06-26  Brian Gough  <[e-mail]>

	* test_sf.c (test_jac): added tests over the full period for
	elljac functions

2005-05-23  Brian Gough  <[e-mail]>

	* test_bessel.c (test_bessel): added test for steed(99,1,...)

	* legendre_H3d.c (legendre_H3d_CF1): use hypot
	(legendre_H3d_CF1_ser): use hypot
	(gsl_sf_legendre_H3d_e): use hypot
	(gsl_sf_legendre_H3d_e): use hypot
	(gsl_sf_legendre_H3d_array): use hypot

	* dilog.c (dilogc_unitdisk): use hypot

	* coulomb.c (gsl_sf_coulomb_CL_array): use hypot
	(coulomb_F_recur): use hypot
	(coulomb_G_recur): use hypot
	(coulomb_jwkb): use hypot
	(gsl_sf_coulomb_wave_F_array): use hypot
	(gsl_sf_coulomb_wave_FG_array): use hypot
	(gsl_sf_coulomb_wave_FGp_array): use hypot

	* bessel_j.c (gsl_sf_bessel_jl_steed_array): use hypot

	* bessel.c (gsl_sf_bessel_Inu_scaled_asymp_unif_e): use hypot
	(gsl_sf_bessel_Knu_scaled_asymp_unif_e): use hypot

2005-03-02  Brian Gough  <[e-mail]>

	* coulomb_bound.c (gsl_sf_hydrogenicR_e): don't check for
	underflow when function is known to be zero (e.g. r=0 l>0 or at
	zeroes of the laguerre polynomial).

2004-12-29  Brian Gough  <[e-mail]>

	* dilog.c (gsl_sf_complex_dilog_e): use const consistently in
	arguments of declaration and definition
	(gsl_sf_complex_dilog_xy_e): as above

2004-12-26  Brian Gough  <[e-mail]>

	* gamma_inc.c (gamma_inc_D): improve error estimate for case of
	u=x/a to include cancellation errors and only use it when x < 0.5*a
	since the cancellation errors are significant for x/a ~ 1

2004-12-23  Brian Gough  <[e-mail]>

	* gsl_sf_coupling.h: fixed declaration to
	gsl_sf_coupling_6j_INCORRECT instead of
	gsl_sf_coupling_INCORRECT_6j

2004-11-12  Brian Gough  <[e-mail]>

	* psi.c (gsl_sf_psi_1): added missing function definition
	gsl_sf_psi_1

2004-10-11  Brian Gough  <[e-mail]>

	* expint.c (gsl_sf_expint_Ei_scaled): fixed call to incorrect
	function gsl_sf_expint_Ei_e

2004-06-03  Brian Gough  <[e-mail]>

	* psi.c (psi_n_xg0): added missing return type int

2003-11-30  Brian Gough  <[e-mail]>

	* gsl_sf_log.h: added missing headers for inline functions

2003-08-11  Brian Gough  <[e-mail]>

	* test_sf.c: added preprocessor definitions TEST_FACTOR and
	TEST_SIGMA to allow larger tolerances on released versions (to
	reduce the number of spurious bug reports).

2003-07-24  Brian Gough  <[e-mail]>