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diff --git a/gsl-1.9/specfunc/bessel_k.c b/gsl-1.9/specfunc/bessel_k.c
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+/* specfunc/bessel_k.c
+ *
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000 Gerard Jungman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/* Author: G. Jungman */
+
+#include <config.h>
+#include <gsl/gsl_math.h>
+#include <gsl/gsl_errno.h>
+#include <gsl/gsl_sf_pow_int.h>
+#include <gsl/gsl_sf_gamma.h>
+#include <gsl/gsl_sf_bessel.h>
+
+#include "error.h"
+#include "check.h"
+
+#include "bessel.h"
+
+/*-*-*-*-*-*-*-*-*-*-*-* Private Section *-*-*-*-*-*-*-*-*-*-*-*/
+
+/* [Abramowitz+Stegun, 10.2.4 + 10.2.6]
+ * with lmax=15, precision ~ 15D for x < 3
+ *
+ * assumes l >= 1
+ */
+static int bessel_kl_scaled_small_x(int l, const double x, gsl_sf_result * result)
+{
+ gsl_sf_result num_fact;
+ double den = gsl_sf_pow_int(x, l+1);
+ int stat_df = gsl_sf_doublefact_e((unsigned int) (2*l-1), &num_fact);
+
+ if(stat_df != GSL_SUCCESS || den == 0.0) {
+ OVERFLOW_ERROR(result);
+ }
+ else {
+ const int lmax = 50;
+ gsl_sf_result ipos_term;
+ double ineg_term;
+ double sgn = (GSL_IS_ODD(l) ? -1.0 : 1.0);
+ double ex = exp(x);
+ double t = 0.5*x*x;
+ double sum = 1.0;
+ double t_coeff = 1.0;
+ double t_power = 1.0;
+ double delta;
+ int stat_il;
+ int i;
+
+ for(i=1; i<lmax; i++) {
+ t_coeff /= i*(2*(i-l) - 1);
+ t_power *= t;
+ delta = t_power*t_coeff;
+ sum += delta;
+ if(fabs(delta/sum) < GSL_DBL_EPSILON) break;
+ }
+
+ stat_il = gsl_sf_bessel_il_scaled_e(l, x, &ipos_term);
+ ineg_term = sgn * num_fact.val/den * sum;
+ result->val = -sgn * 0.5*M_PI * (ex*ipos_term.val - ineg_term);
+ result->val *= ex;
+ result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ return stat_il;
+ }
+}
+
+
+/*-*-*-*-*-*-*-*-*-*-*-* Functions with Error Codes *-*-*-*-*-*-*-*-*-*-*-*/
+
+int gsl_sf_bessel_k0_scaled_e(const double x, gsl_sf_result * result)
+{
+ /* CHECK_POINTER(result) */
+
+ if(x <= 0.0) {
+ DOMAIN_ERROR(result);
+ }
+ else {
+ result->val = M_PI/(2.0*x);
+ result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ CHECK_UNDERFLOW(result);
+ return GSL_SUCCESS;
+ }
+}
+
+
+int gsl_sf_bessel_k1_scaled_e(const double x, gsl_sf_result * result)
+{
+ /* CHECK_POINTER(result) */
+
+ if(x <= 0.0) {
+ DOMAIN_ERROR(result);
+ }
+ else if(x < (M_SQRTPI+1.0)/(M_SQRT2*GSL_SQRT_DBL_MAX)) {
+ OVERFLOW_ERROR(result);
+ }
+ else {
+ result->val = M_PI/(2.0*x) * (1.0 + 1.0/x);
+ result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ CHECK_UNDERFLOW(result);
+ return GSL_SUCCESS;
+ }
+}
+
+
+int gsl_sf_bessel_k2_scaled_e(const double x, gsl_sf_result * result)
+{
+ /* CHECK_POINTER(result) */
+
+ if(x <= 0.0) {
+ DOMAIN_ERROR(result);
+ }
+ else if(x < 2.0/GSL_ROOT3_DBL_MAX) {
+ OVERFLOW_ERROR(result);
+ }
+ else {
+ result->val = M_PI/(2.0*x) * (1.0 + 3.0/x * (1.0 + 1.0/x));
+ result->err = 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ CHECK_UNDERFLOW(result);
+ return GSL_SUCCESS;
+ }
+}
+
+
+int gsl_sf_bessel_kl_scaled_e(int l, const double x, gsl_sf_result * result)
+{
+ if(l < 0 || x <= 0.0) {
+ DOMAIN_ERROR(result);
+ }
+ else if(l == 0) {
+ return gsl_sf_bessel_k0_scaled_e(x, result);
+ }
+ else if(l == 1) {
+ return gsl_sf_bessel_k1_scaled_e(x, result);
+ }
+ else if(l == 2) {
+ return gsl_sf_bessel_k2_scaled_e(x, result);
+ }
+ else if(x < 3.0) {
+ return bessel_kl_scaled_small_x(l, x, result);
+ }
+ else if(GSL_ROOT3_DBL_EPSILON * x > (l*l + l + 1)) {
+ int status = gsl_sf_bessel_Knu_scaled_asympx_e(l + 0.5, x, result);
+ double pre = sqrt((0.5*M_PI)/x);
+ result->val *= pre;
+ result->err *= pre;
+ return status;
+ }
+ else if(GSL_MIN(0.29/(l*l+1.0), 0.5/(l*l+1.0+x*x)) < GSL_ROOT3_DBL_EPSILON) {
+ int status = gsl_sf_bessel_Knu_scaled_asymp_unif_e(l + 0.5, x, result);
+ double pre = sqrt((0.5*M_PI)/x);
+ result->val *= pre;
+ result->err *= pre;
+ return status;
+ }
+ else {
+ /* recurse upward */
+ gsl_sf_result r_bk;
+ gsl_sf_result r_bkm;
+ int stat_1 = gsl_sf_bessel_k1_scaled_e(x, &r_bk);
+ int stat_0 = gsl_sf_bessel_k0_scaled_e(x, &r_bkm);
+ double bkp;
+ double bk = r_bk.val;
+ double bkm = r_bkm.val;
+ int j;
+ for(j=1; j<l; j++) {
+ bkp = (2*j+1)/x*bk + bkm;
+ bkm = bk;
+ bk = bkp;
+ }
+ result->val = bk;
+ result->err = fabs(bk) * (fabs(r_bk.err/r_bk.val) + fabs(r_bkm.err/r_bkm.val));
+ result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+
+ return GSL_ERROR_SELECT_2(stat_1, stat_0);
+ }
+}
+
+int
+gsl_sf_bessel_kl_scaled_array(const int lmax, const double x, double * result_array)
+{
+ if(lmax < 0 || x <= 0.0) {
+ GSL_ERROR("domain error", GSL_EDOM);
+ } else if (lmax == 0) {
+ gsl_sf_result result;
+ int stat = gsl_sf_bessel_k0_scaled_e(x, &result);
+ result_array[0] = result.val;
+ return stat;
+ } else {
+ int ell;
+ double kellp1, kell, kellm1;
+ gsl_sf_result r_kell;
+ gsl_sf_result r_kellm1;
+ gsl_sf_bessel_k1_scaled_e(x, &r_kell);
+ gsl_sf_bessel_k0_scaled_e(x, &r_kellm1);
+ kell = r_kell.val;
+ kellm1 = r_kellm1.val;
+ result_array[0] = kellm1;
+ result_array[1] = kell;
+ for(ell = 1; ell < lmax; ell++) {
+ kellp1 = (2*ell+1)/x * kell + kellm1;
+ result_array[ell+1] = kellp1;
+ kellm1 = kell;
+ kell = kellp1;
+ }
+ return GSL_SUCCESS;
+ }
+}
+
+
+/*-*-*-*-*-*-*-*-*-* Functions w/ Natural Prototypes *-*-*-*-*-*-*-*-*-*-*/
+
+#include "eval.h"
+
+double gsl_sf_bessel_k0_scaled(const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_k0_scaled_e(x, &result));
+}
+
+double gsl_sf_bessel_k1_scaled(const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_k1_scaled_e(x, &result));
+}
+
+double gsl_sf_bessel_k2_scaled(const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_k2_scaled_e(x, &result));
+}
+
+double gsl_sf_bessel_kl_scaled(const int l, const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_kl_scaled_e(l, x, &result));
+}
+
+
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