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diff --git a/gsl-1.9/specfunc/bessel_In.c b/gsl-1.9/specfunc/bessel_In.c
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+/* specfunc/bessel_In.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_bessel.h>
+
+#include "error.h"
+
+#include "bessel.h"
+
+/*-*-*-*-*-*-*-*-*-*-*-* Functions with Error Codes *-*-*-*-*-*-*-*-*-*-*-*/
+
+
+int
+gsl_sf_bessel_In_scaled_e(int n, const double x, gsl_sf_result * result)
+{
+ const double ax = fabs(x);
+
+ n = abs(n); /* I(-n, z) = I(n, z) */
+
+ /* CHECK_POINTER(result) */
+
+ if(n == 0) {
+ return gsl_sf_bessel_I0_scaled_e(x, result);
+ }
+ else if(n == 1) {
+ return gsl_sf_bessel_I1_scaled_e(x, result);
+ }
+ else if(x == 0.0) {
+ result->val = 0.0;
+ result->err = 0.0;
+ return GSL_SUCCESS;
+ }
+ else if(x*x < 10.0*(n+1.0)/M_E) {
+ gsl_sf_result t;
+ double ex = exp(-ax);
+ int stat_In = gsl_sf_bessel_IJ_taylor_e((double)n, ax, 1, 50, GSL_DBL_EPSILON, &t);
+ result->val = t.val * ex;
+ result->err = t.err * ex;
+ result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ if(x < 0.0 && GSL_IS_ODD(n)) result->val = -result->val;
+ return stat_In;
+ }
+ else if(n < 150 && ax < 1e7) {
+ gsl_sf_result I0_scaled;
+ int stat_I0 = gsl_sf_bessel_I0_scaled_e(ax, &I0_scaled);
+ double rat;
+ int stat_CF1 = gsl_sf_bessel_I_CF1_ser((double)n, ax, &rat);
+ double Ikp1 = rat * GSL_SQRT_DBL_MIN;
+ double Ik = GSL_SQRT_DBL_MIN;
+ double Ikm1;
+ int k;
+ for(k=n; k >= 1; k--) {
+ Ikm1 = Ikp1 + 2.0*k/ax * Ik;
+ Ikp1 = Ik;
+ Ik = Ikm1;
+ }
+ result->val = I0_scaled.val * (GSL_SQRT_DBL_MIN / Ik);
+ result->err = I0_scaled.err * (GSL_SQRT_DBL_MIN / Ik);
+ result->err += 2.0 * GSL_DBL_EPSILON * fabs(result->val);
+ if(x < 0.0 && GSL_IS_ODD(n)) result->val = -result->val;
+ return GSL_ERROR_SELECT_2(stat_I0, stat_CF1);
+ }
+ else if( GSL_MIN( 0.29/(n*n), 0.5/(n*n + x*x) ) < 0.5*GSL_ROOT3_DBL_EPSILON) {
+ int stat_as = gsl_sf_bessel_Inu_scaled_asymp_unif_e((double)n, ax, result);
+ if(x < 0.0 && GSL_IS_ODD(n)) result->val = -result->val;
+ return stat_as;
+ }
+ else {
+ const int nhi = 2 + (int) (1.2 / GSL_ROOT6_DBL_EPSILON);
+ gsl_sf_result r_Ikp1;
+ gsl_sf_result r_Ik;
+ int stat_a1 = gsl_sf_bessel_Inu_scaled_asymp_unif_e(nhi+1.0, ax, &r_Ikp1);
+ int stat_a2 = gsl_sf_bessel_Inu_scaled_asymp_unif_e((double)nhi, ax, &r_Ik);
+ double Ikp1 = r_Ikp1.val;
+ double Ik = r_Ik.val;
+ double Ikm1;
+ int k;
+ for(k=nhi; k > n; k--) {
+ Ikm1 = Ikp1 + 2.0*k/ax * Ik;
+ Ikp1 = Ik;
+ Ik = Ikm1;
+ }
+ result->val = Ik;
+ result->err = Ik * (r_Ikp1.err/r_Ikp1.val + r_Ik.err/r_Ik.val);
+ if(x < 0.0 && GSL_IS_ODD(n)) result->val = -result->val;
+ return GSL_ERROR_SELECT_2(stat_a1, stat_a2);
+ }
+}
+
+
+int
+gsl_sf_bessel_In_scaled_array(const int nmin, const int nmax, const double x, double * result_array)
+{
+ /* CHECK_POINTER(result_array) */
+
+ if(nmax < nmin || nmin < 0) {
+ int j;
+ for(j=0; j<=nmax-nmin; j++) result_array[j] = 0.0;
+ GSL_ERROR ("domain error", GSL_EDOM);
+ }
+ else if(x == 0.0) {
+ int j;
+ for(j=0; j<=nmax-nmin; j++) result_array[j] = 0.0;
+ if(nmin == 0) result_array[0] = 1.0;
+ return GSL_SUCCESS;
+ }
+ else if(nmax == 0) {
+ gsl_sf_result I0_scaled;
+ int stat = gsl_sf_bessel_I0_scaled_e(x, &I0_scaled);
+ result_array[0] = I0_scaled.val;
+ return stat;
+ }
+ else {
+ const double ax = fabs(x);
+ const double two_over_x = 2.0/ax;
+
+ /* starting values */
+ gsl_sf_result r_Inp1;
+ gsl_sf_result r_In;
+ int stat_0 = gsl_sf_bessel_In_scaled_e(nmax+1, ax, &r_Inp1);
+ int stat_1 = gsl_sf_bessel_In_scaled_e(nmax, ax, &r_In);
+ double Inp1 = r_Inp1.val;
+ double In = r_In.val;
+ double Inm1;
+ int n;
+
+ for(n=nmax; n>=nmin; n--) {
+ result_array[n-nmin] = In;
+ Inm1 = Inp1 + n * two_over_x * In;
+ Inp1 = In;
+ In = Inm1;
+ }
+
+ /* deal with signs */
+ if(x < 0.0) {
+ for(n=nmin; n<=nmax; n++) {
+ if(GSL_IS_ODD(n)) result_array[n-nmin] = -result_array[n-nmin];
+ }
+ }
+
+ return GSL_ERROR_SELECT_2(stat_0, stat_1);
+ }
+}
+
+
+int
+gsl_sf_bessel_In_e(const int n_in, const double x, gsl_sf_result * result)
+{
+ const double ax = fabs(x);
+ const int n = abs(n_in); /* I(-n, z) = I(n, z) */
+ gsl_sf_result In_scaled;
+ const int stat_In_scaled = gsl_sf_bessel_In_scaled_e(n, ax, &In_scaled);
+
+ /* In_scaled is always less than 1,
+ * so this overflow check is conservative.
+ */
+ if(ax > GSL_LOG_DBL_MAX - 1.0) {
+ OVERFLOW_ERROR(result);
+ }
+ else {
+ const double ex = exp(ax);
+ result->val = ex * In_scaled.val;
+ result->err = ex * In_scaled.err;
+ result->err += ax * GSL_DBL_EPSILON * fabs(result->val);
+ if(x < 0.0 && GSL_IS_ODD(n)) result->val = -result->val;
+ return stat_In_scaled;
+ }
+}
+
+
+int
+gsl_sf_bessel_In_array(const int nmin, const int nmax, const double x, double * result_array)
+{
+ double ax = fabs(x);
+
+ /* CHECK_POINTER(result_array) */
+
+ if(ax > GSL_LOG_DBL_MAX - 1.0) {
+ int j;
+ for(j=0; j<=nmax-nmin; j++) result_array[j] = 0.0; /* FIXME: should be Inf */
+ GSL_ERROR ("overflow", GSL_EOVRFLW);
+ }
+ else {
+ int j;
+ double eax = exp(ax);
+ int status = gsl_sf_bessel_In_scaled_array(nmin, nmax, x, result_array);
+ for(j=0; j<=nmax-nmin; j++) result_array[j] *= eax;
+ return status;
+ }
+}
+
+/*-*-*-*-*-*-*-*-*-* Functions w/ Natural Prototypes *-*-*-*-*-*-*-*-*-*-*/
+
+#include "eval.h"
+
+double gsl_sf_bessel_In_scaled(const int n, const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_In_scaled_e(n, x, &result));
+}
+
+double gsl_sf_bessel_In(const int n, const double x)
+{
+ EVAL_RESULT(gsl_sf_bessel_In_e(n, x, &result));
+}
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