1 /* tj1 -- test file for the Bessel function of first kind (order 1) 2 3 Copyright 2007-2020 Free Software Foundation, Inc. 4 Contributed by the AriC and Caramba projects, INRIA. 5 6 This file is part of the GNU MPFR Library. 7 8 The GNU MPFR Library is free software; you can redistribute it and/or modify 9 it under the terms of the GNU Lesser General Public License as published by 10 the Free Software Foundation; either version 3 of the License, or (at your 11 option) any later version. 12 13 The GNU MPFR Library is distributed in the hope that it will be useful, but 14 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 16 License for more details. 17 18 You should have received a copy of the GNU Lesser General Public License 19 along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 20 https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 21 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 22 23 #include "mpfr-test.h" 24 25 #define TEST_FUNCTION mpfr_j1 26 #define RAND_FUNCTION(x) mpfr_random2(x, MPFR_LIMB_SIZE (x), 8, RANDS) 27 #define REDUCE_EMAX 262143 /* otherwise arg. reduction is too expensive */ 28 #include "tgeneric.c" 29 30 /* test for small input, where j1(x) = x/2 - x^3/16 + ... */ 31 static void 32 test_small (void) 33 { 34 mpfr_t x, y; 35 int inex, sign; 36 mpfr_exp_t e, emin; 37 38 mpfr_init2 (x, 10); 39 mpfr_init2 (y, 9); 40 emin = mpfr_get_emin (); 41 for (e = -4; e >= -30; e--) 42 { 43 if (e == -30) 44 { 45 e = mpfr_get_emin_min () - 1; 46 mpfr_set_emin (e + 1); 47 } 48 for (sign = -1; sign <= 1; sign += 2) 49 { 50 mpfr_set_si_2exp (x, sign, e, MPFR_RNDN); 51 mpfr_nexttoinf (x); 52 inex = mpfr_j1 (y, x, MPFR_RNDN); 53 if (e >= -29) 54 { 55 /* since |x| is just above 2^e, |j1(x)| is just above 2^(e-1), 56 thus y should be 2^(e-1) and the inexact flag should be 57 of opposite sign of x */ 58 MPFR_ASSERTN(mpfr_cmp_si_2exp (y, sign, e - 1) == 0); 59 MPFR_ASSERTN(VSIGN (inex) * sign < 0); 60 } 61 else 62 { 63 /* here |y| should be 0.5*2^emin and the inexact flag should 64 have the sign of x */ 65 MPFR_ASSERTN(mpfr_cmp_si_2exp (y, sign, e) == 0); 66 MPFR_ASSERTN(VSIGN (inex) * sign > 0); 67 } 68 } 69 } 70 mpfr_set_emin (emin); 71 mpfr_clear (x); 72 mpfr_clear (y); 73 } 74 75 int 76 main (int argc, char *argv[]) 77 { 78 mpfr_t x, y; 79 80 tests_start_mpfr (); 81 82 test_small (); 83 84 mpfr_init (x); 85 mpfr_init (y); 86 87 /* special values */ 88 mpfr_set_nan (x); 89 mpfr_j1 (y, x, MPFR_RNDN); 90 MPFR_ASSERTN(mpfr_nan_p (y)); 91 92 mpfr_set_inf (x, 1); /* +Inf */ 93 mpfr_j1 (y, x, MPFR_RNDN); 94 MPFR_ASSERTN(mpfr_cmp_ui (y, 0) == 0 && MPFR_IS_POS (y)); 95 96 mpfr_set_inf (x, -1); /* -Inf */ 97 mpfr_j1 (y, x, MPFR_RNDN); 98 MPFR_ASSERTN(mpfr_cmp_ui (y, 0) == 0 && MPFR_IS_POS (y)); 99 100 mpfr_set_ui (x, 0, MPFR_RNDN); /* +0 */ 101 mpfr_j1 (y, x, MPFR_RNDN); 102 MPFR_ASSERTN(mpfr_cmp_ui (y, 0) == 0 && MPFR_IS_POS (y)); /* j1(+0)=+0 */ 103 104 mpfr_set_ui (x, 0, MPFR_RNDN); 105 mpfr_neg (x, x, MPFR_RNDN); /* -0 */ 106 mpfr_j1 (y, x, MPFR_RNDN); 107 MPFR_ASSERTN(mpfr_cmp_ui (y, 0) == 0 && MPFR_IS_NEG (y)); /* j1(-0)=-0 */ 108 109 mpfr_set_prec (x, 53); 110 mpfr_set_prec (y, 53); 111 112 mpfr_set_ui (x, 1, MPFR_RNDN); 113 mpfr_j1 (y, x, MPFR_RNDN); 114 mpfr_set_str_binary (x, "0.0111000010100111001001111011101001011100001100011011"); 115 if (mpfr_cmp (x, y)) 116 { 117 printf ("Error in mpfr_j1 for x=1, rnd=MPFR_RNDN\n"); 118 printf ("Expected "); mpfr_dump (x); 119 printf ("Got "); mpfr_dump (y); 120 exit (1); 121 } 122 mpfr_clear (x); 123 mpfr_clear (y); 124 125 test_generic (MPFR_PREC_MIN, 100, 10); 126 127 data_check ("data/j1", mpfr_j1, "mpfr_j1"); 128 129 tests_end_mpfr (); 130 131 return 0; 132 } 133