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GNU Scientific Library,C语言开发的数值方面的函数库

* What is new in gsl-1.6:

** Added a new wavelet directory, with 1-dimensional and 2-dimensional
discrete wavelet transforms.

** Added support for LQ and P^T LQ decompositions.  To find the QR
decomposition of large systems (M>>N) use the LQ decomposition,
solving the transpose of the original system.  This allows more
efficient memory access, and is useful for solving large least-squares
problems.

** Fixed a bug in the SYRK and HERK blas functions gsl_blas_{s,d,c,z}syrk 
and gsl_blas_{c,z}herk which caused invalid memory access for non-square 
matrices.

** Fixed a bug in gsl_swap_vectors which caused it to return incorrect
results when swapping vectors with different strides.

** Corrected the error estimate for gsl_cheb_eval_n_err to use
evaluation order instead of the approximation order.

** Improved the reliability of the gsl_sf_gamma_inc family of
functions.

** Equal abscissae are now handled gracefully in the cspline and
periodic cspline interpolations.

** Removed potential cancellation error in calculation of uniform
histogram ranges.

** Improved numerical stability of integration for akima and cspline
interpolation.

** Differential equation solvers now handle error codes returned from
user-defined functions.

** Improved error estimates in ode-initval solvers, and provide exact
derivatives on output.  Added new semi-implicit ode-initval solver,
gsl_odeiv_step_rk2simp.

** Added missing function definition for gsl_sf_psi_1.

** Fixed the function gsl_sf_expint_Ei_scaled to call
gsl_sf_expint_Ei_scaled_e instead of gsl_sf_expint_Ei_e.

** Added cumulative distribution function for exponential power
distribution.

** The functions gsl_cdf_beta_P and gsl_cdf_beta_Q now return
consistent results of 0 or 1 for out of range values, x<0 and x>1,
rather than 0 for left and right tails simultaneously.

** The Jacobi eigensolvers gsl_eigen_jacobi and gsl_eigen_jacobi_invert 
have new implementations from Golub and Van Loan.

** The standard output and standard error streams are now flushed by
the default error handler before the program aborts, in order to
ensure that error messages are properly displayed on some platforms.

* What was new in gsl-1.5:

** Multifit routines now handle iterations where |f| is already
minimised to zero, without division by zero.

** Fixed the singular value tolerance test in the multifit covariance
calculation from < to <= to match the original MINPACK code.

** The macro HAVE_INLINE is now tested with #ifdef instead of #if as
in versions prior to 1.4, to match the documentation, and the macro
GSL_RANGE_CHECK_OFF now works correctly.  An alternative macro
GSL_RANGE_CHECK={0,1} can be used to control range-checking.

** Fixed a potential array overflow in gsl_ran_landau.

** Fixed a small discrepancy in the tolerance calculation of the
one-dimensional brent minimiser.

** Numerical derivatives should now be calculated using the
gsl_deriv_forward, gsl_deriv_central and gsl_deriv_backward functions,
which accept a step-size argument in addition to the position x.  The
original gsl_diff functions (without the step-size) are deprecated.

** Corrected documentation for gsl_ran_hypergeometric_pdf()

** The tridiagonal matrix solvers gsl_linalg_solve_symm_tridiag,
gsl_linalg_solve_tridiag, gsl_linalg_solve_symm_cyc_tridiag,
gsl_linalg_solve_cyc_tridiag now use the GSL_ERROR macro to report
errors, instead of simply returning an error code.  The arguments to
these functions must now use exact lengths with no additional
elements.  For cyclic systems all vectors must be of length N, for
tridiagonal systems the offdiagonal elements must be of length N-1.

** The singular value decomposition routines gsl_linalg_SV_decomp and
gsl_linalg_SV_decomp_mod now handle the SVD of a column vector (N=1,
arbitrary M), which can occur in linear fitting.

** Restored missing header files gsl_const_mks.h and gsl_const_cgs.h.
The incorrect values of the electrical units for gsl_const_cgs
(VACUUM_PERMEABILITY and VACUUM_PERMITTIVITY) have been removed.

** Fixed gsl_linalg_SV_decomp() to avoid an infinite loop when
computing the SVD of matrices containing Inf and Nan.

** Fixed gsl_linalg_balance_columns() to avoid an infinite loop when
rescaling matrices containing Inf and NaN.

** Fixed header file <gsl/gsl_sf_log.h> to include declarations for 
error codes in inline versions of gsl_sf_log functions

** Fixed header file <gsl/gsl_const.h> to include new MKSA and CGSM
header files.

** Added Stefan-Boltzmann constant and Thomson cross section to
physical constants

* What was new in gsl-1.4:

** Added cumulative distribution functions and their inverses for the
continuous random distributions including: gaussian, lognormal, gamma,
beta, cauchy, laplace, chisq, exponential, gumbel, weibull,
F-distribution, t-distribution, logistic, pareto and rayleigh.

** Added faster binomial random variates using the TPE rejection
algorithm, in the function gsl_randist_binomial_tpe.

** Added new functions gsl_rng_fwrite and gsl_rnd_fread for storing
the state of random number generators in a file.

** Added a new function gsl_combination_memcpy()

** Corrected values of electrical constants in CGS units.  To take
account of different electrical systems of units the values are now
prefixed by GSL_CONST_MKSA (for the SI Metre, Kilogram, Second, Ampere
system) or GSL_CONST_CGSM (for the Centimetre, Gram, Second, Magnetic
system with the Gauss as the fundamental unit of magnetic field
strength).  The previous GSL_CONST_MKS and GSL_CONST_CGS prefixes have
been removed, as have the permeability and permittivity constants in
the CGS system since this uses different defining equations.

** Fixed bugs in the random number generators gsl_rng_fishman18,
gsl_rng_fishman2x, and gsl_rng_knuthran2 which caused them to return
incorrect results.  Minor corrections were made to the parameters in
the other Knuth generators borosh13, coveyou, fishman20, lecuyer21,
and waterman14.

** Fixed a missing transpose bug in the gsl_linalg_QR_QRsolve
and gsl_linalg_QRPT_QRsolve routines which were computing the
solution to Q^T R x = b instead of Q R x = b.

** Fixed gsl_sf_gammainv to return zero instead of a domain
error for arguments corresponding to singularities in gamma.

** Fixed a bug in the simplex minimization algorithm which
caused it to fail to find the second highest point correctly
when searching the set of simplex points.

** Fixed a bug in the conjugate gradient minimizers conjugate_pr,
conjugate_fr and vector_bgfs which caused the search
directions to be updated incorrectly.

** Fixed a bug in gsl_sf_psi_1_int(1) which caused it to
return the incorrect sign for psi(1,1).

** Fixed the simulated annealing routine gsl_siman_solve to use the
parameter iters_fixed_T for the number of iterations at fixed
temperature instead of n_tries.

** Fixed a bug in gsl_combination_valid which caused it to return the
incorrect status.

** Fixed a bug in gsl_permutation_canonical_to_linear which caused the
output to always be zero, and the input permutation to be incorrectly
replaced by the output.

** Fixed a bug is gsl_ran_discrete which could cause uninitialised
data to be returned for some distributions.

** Fixed the dependencies for gsl_chebyshev.h to include gsl_math.h.

** Fixed a bug in gsl_complex_arccsc_real which caused it to return 
the incorrect sign for the imaginary part when -1<x<0.

** Fixed a bug in the QAWC Cauchy integration routine which could
allow the singularity to fall on an interval boundary, leading to
division by zero.

** Improved gsl_sf_gamma_inc_P(a,x) to avoid a domain error for x<<a
when a>10.

** Improved the accuracy of gsl_sf_coupling_3j for large arguments.

** Improved the performance of gsl_sf_choose(m,n) by separating the
calculations for small and large arguments.

** On platforms without IEEE comparisons gsl_{isnan,isinf,finite} will
fall back to the system versions of isnan, isinf and finite if
available.

** gsl_linalg_householder_hv now uses BLAS routines internally

** The script configure.in is now compatible with autoconf-2.50 and
later.

** Reduced the memory usage of the multifit algorithms from MxM to MxN
for large M by performing the QR decomposition of the Jacobian
in-place.

** IEEE modes now use the C99 fenv.h functions when platform spectific
functions are not available.

* What was new in gsl-1.3:

** Changed interface for gsl_sf_coupling_6j...(...). The old functions
actually calculated 6j for a permutation of the arguments (that
related to Racah W). This was incorrect and not consistent with
the documentation. The new versions calculate < {a,b,c}, {d,e,f} >,
as stated in the documentation. The old versions are still available
as gsl_sf_coupling_6j_INCORRECT...(...), though they are deprecated
and will be removed at some point in the future.

** Added new functions for computing Em(x)=exp(-x)*Ei(x), the modified
(scaled) form of the exponential integral, gsl_sf_expint_E1_scaled,
gsl_sf_expint_E2_scaled, gsl_sf_expint_Ei_scaled.
   
** Fixed compilation problems with gcc -ansi and other ANSI compilers.

** Fixed uninitialized memory access in the Niederreiter quasi-random
number generator.

** Fixed the eigenvalue routines to prevent an infinite loop for Inf
or NaN entries in matrix.

** Fixed a bug in the multifit and multiroots allocation routines
which cause them to fail to report some out of memory conditions.

** Fixed a bug in the seeding for the random number generator
gsl_rng_taus2 which affected a small number of seeds.

** Modified the complex householder transforms to avoid division by
zero, which could cause NaNs to be returned by the gsl_eigen_hermv
eigenvalue decomposition.

** The Nelder-Mead simplex algorithm for multidimensional 
minimisation has been added.

** The random number distributions now include the Dirichlet and
Multinomial distributions.

** Added a new function gsl_fcmp for approximate comparison of
floating point numbers using Knuth's algorithm.

** Added new functions gsl_ldexp and gsl_frexp as portable
alternatives to ldexp() and frexp().

** Fixed a bug in gsl_linalg_bidiag_unpack_B which was returning
incorrect results for the superdiagonal.

** Fixed a bug in the acceptance condition for simulated annealing

** Ordinary differential equations can now be solved using a different
absolute error for each component with gsl_odeiv_control_scaled_new().

** Upgraded to libtool-1.4.3

* What was new in gsl-1.2:

** Added new functions for combining permutations, converting between
cyclic and linear representations, and counting cycles and inversions.

** New multiroot functions now allow access to the current values of f
and dx.

** The default error handler now outputs a explanatory message before
aborting.

** Extended gsl_linalg_SV_decomp to handle exact zeroes in the
singular values, and added tests for 3x3 matrices.

** Fixed a bug in gsl_linalg_SV_decomp which caused singular values to
be sorted incorrectly.

** Fixed a bug in gsl_linalg_solv_symm_cyc_tridiag which caused it to
produce incorrect results.

** Added nonsymmetric tridiagonal solvers gsl_linalg_solve_tridiag and
gsl_linalg_solve_cyc_tridiag.

** The declarations used to export static objects can now be
controlled through a macro GSL_VAR and the header file
<gsl/gsl_types.h>.