[270] | 1 | /*
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| 2 | ** math.c - Math module
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| 3 | **
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| 4 | ** See Copyright Notice in mruby.h
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| 5 | */
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| 6 |
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[439] | 7 | #ifdef MRB_WITHOUT_FLOAT
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| 8 | # error Math conflicts 'MRB_WITHOUT_FLOAT' configuration in your 'build_config.rb'
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| 9 | #endif
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| 10 |
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[331] | 11 | #include <mruby.h>
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| 12 | #include <mruby/array.h>
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[270] | 13 |
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| 14 | #include <math.h>
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| 15 |
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| 16 | static void
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| 17 | domain_error(mrb_state *mrb, const char *func)
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| 18 | {
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| 19 | struct RClass *math = mrb_module_get(mrb, "Math");
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| 20 | struct RClass *domainerror = mrb_class_get_under(mrb, math, "DomainError");
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[439] | 21 | mrb_raisef(mrb, domainerror, "Numerical argument is out of domain - %s", func);
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[270] | 22 | }
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| 23 |
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| 24 | /* math functions not provided by Microsoft Visual C++ 2012 or older */
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[331] | 25 | #if defined _MSC_VER && _MSC_VER <= 1700
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[270] | 26 |
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| 27 | #include <float.h>
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| 28 |
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| 29 | double
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| 30 | asinh(double x)
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| 31 | {
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| 32 | double xa, ya, y;
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| 33 |
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| 34 | /* Basic formula loses precision for x < 0, but asinh is an odd function */
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| 35 | xa = fabs(x);
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| 36 | if (xa > 3.16227E+18) {
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| 37 | /* Prevent x*x from overflowing; basic formula reduces to log(2*x) */
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| 38 | ya = log(xa) + 0.69314718055994530942;
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| 39 | }
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| 40 | else {
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| 41 | /* Basic formula for asinh */
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| 42 | ya = log(xa + sqrt(xa*xa + 1.0));
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| 43 | }
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| 44 |
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| 45 | y = _copysign(ya, x);
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| 46 | return y;
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| 47 | }
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| 48 |
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| 49 | double
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| 50 | acosh(double x)
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| 51 | {
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| 52 | double y;
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| 53 |
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| 54 | if (x > 3.16227E+18) {
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| 55 | /* Prevent x*x from overflowing; basic formula reduces to log(2*x) */
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| 56 | y = log(x) + 0.69314718055994530942;
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| 57 | }
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| 58 | else {
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| 59 | /* Basic formula for acosh */
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| 60 | y = log(x + sqrt(x*x - 1.0));
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| 61 | }
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| 62 |
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| 63 | return y;
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| 64 | }
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| 65 |
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| 66 | double
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| 67 | atanh(double x)
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| 68 | {
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| 69 | double y;
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| 70 |
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| 71 | if (fabs(x) < 1E-2) {
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| 72 | /* The sums 1+x and 1-x lose precision for small x. Use the polynomial
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| 73 | instead. */
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| 74 | double x2 = x * x;
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| 75 | y = x*(1.0 + x2*(1.0/3.0 + x2*(1.0/5.0 + x2*(1.0/7.0))));
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| 76 | }
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| 77 | else {
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| 78 | /* Basic formula for atanh */
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| 79 | y = 0.5 * (log(1.0+x) - log(1.0-x));
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| 80 | }
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| 81 |
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| 82 | return y;
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| 83 | }
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| 84 |
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| 85 | double
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| 86 | cbrt(double x)
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| 87 | {
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| 88 | double xa, ya, y;
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| 89 |
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| 90 | /* pow(x, y) is undefined for x < 0 and y not an integer, but cbrt is an
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| 91 | odd function */
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| 92 | xa = fabs(x);
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| 93 | ya = pow(xa, 1.0/3.0);
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| 94 | y = _copysign(ya, x);
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| 95 | return y;
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| 96 | }
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| 97 |
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| 98 | /* Declaration of complementary Error function */
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| 99 | double
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| 100 | erfc(double x);
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| 101 |
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| 102 | /*
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| 103 | ** Implementations of error functions
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| 104 | ** credits to http://www.digitalmars.com/archives/cplusplus/3634.html
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| 105 | */
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| 106 |
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| 107 | /* Implementation of Error function */
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| 108 | double
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| 109 | erf(double x)
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| 110 | {
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| 111 | static const double two_sqrtpi = 1.128379167095512574;
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| 112 | double sum = x;
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| 113 | double term = x;
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| 114 | double xsqr = x*x;
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| 115 | int j= 1;
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| 116 | if (fabs(x) > 2.2) {
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| 117 | return 1.0 - erfc(x);
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| 118 | }
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| 119 | do {
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| 120 | term *= xsqr/j;
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| 121 | sum -= term/(2*j+1);
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| 122 | ++j;
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| 123 | term *= xsqr/j;
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| 124 | sum += term/(2*j+1);
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| 125 | ++j;
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[439] | 126 | if (sum == 0) break;
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| 127 | } while (fabs(term/sum) > DBL_EPSILON);
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[270] | 128 | return two_sqrtpi*sum;
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| 129 | }
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| 130 |
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| 131 | /* Implementation of complementary Error function */
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| 132 | double
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| 133 | erfc(double x)
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| 134 | {
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| 135 | static const double one_sqrtpi= 0.564189583547756287;
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| 136 | double a = 1;
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| 137 | double b = x;
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| 138 | double c = x;
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| 139 | double d = x*x+0.5;
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| 140 | double q1;
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| 141 | double q2 = b/d;
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| 142 | double n = 1.0;
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| 143 | double t;
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| 144 | if (fabs(x) < 2.2) {
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| 145 | return 1.0 - erf(x);
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| 146 | }
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| 147 | if (x < 0.0) { /*signbit(x)*/
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| 148 | return 2.0 - erfc(-x);
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| 149 | }
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| 150 | do {
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| 151 | t = a*n+b*x;
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| 152 | a = b;
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| 153 | b = t;
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| 154 | t = c*n+d*x;
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| 155 | c = d;
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| 156 | d = t;
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| 157 | n += 0.5;
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| 158 | q1 = q2;
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| 159 | q2 = b/d;
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[439] | 160 | } while (fabs(q1-q2)/q2 > DBL_EPSILON);
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[270] | 161 | return one_sqrtpi*exp(-x*x)*q2;
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| 162 | }
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| 163 |
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| 164 | #endif
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| 165 |
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[439] | 166 | #if defined __FreeBSD__ && !defined __FreeBSD_version
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| 167 | #include <osreldate.h> /* for __FreeBSD_version */
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| 168 | #endif
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| 169 |
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[270] | 170 | #if (defined _MSC_VER && _MSC_VER < 1800) || defined __ANDROID__ || (defined __FreeBSD__ && __FreeBSD_version < 803000)
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| 171 |
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| 172 | double
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| 173 | log2(double x)
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| 174 | {
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| 175 | return log10(x)/log10(2.0);
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| 176 | }
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| 177 |
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| 178 | #endif
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| 179 |
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| 180 | /*
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| 181 | TRIGONOMETRIC FUNCTIONS
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| 182 | */
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| 183 |
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| 184 | /*
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| 185 | * call-seq:
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| 186 | * Math.sin(x) -> float
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| 187 | *
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| 188 | * Computes the sine of <i>x</i> (expressed in radians). Returns
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| 189 | * -1..1.
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| 190 | */
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| 191 | static mrb_value
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| 192 | math_sin(mrb_state *mrb, mrb_value obj)
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| 193 | {
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| 194 | mrb_float x;
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| 195 |
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| 196 | mrb_get_args(mrb, "f", &x);
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| 197 | x = sin(x);
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| 198 |
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| 199 | return mrb_float_value(mrb, x);
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| 200 | }
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| 201 |
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| 202 | /*
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| 203 | * call-seq:
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| 204 | * Math.cos(x) -> float
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| 205 | *
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| 206 | * Computes the cosine of <i>x</i> (expressed in radians). Returns
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| 207 | * -1..1.
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| 208 | */
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| 209 | static mrb_value
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| 210 | math_cos(mrb_state *mrb, mrb_value obj)
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| 211 | {
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| 212 | mrb_float x;
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| 213 |
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| 214 | mrb_get_args(mrb, "f", &x);
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| 215 | x = cos(x);
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| 216 |
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| 217 | return mrb_float_value(mrb, x);
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| 218 | }
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| 219 |
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| 220 | /*
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| 221 | * call-seq:
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| 222 | * Math.tan(x) -> float
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| 223 | *
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| 224 | * Returns the tangent of <i>x</i> (expressed in radians).
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| 225 | */
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| 226 | static mrb_value
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| 227 | math_tan(mrb_state *mrb, mrb_value obj)
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| 228 | {
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| 229 | mrb_float x;
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| 230 |
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| 231 | mrb_get_args(mrb, "f", &x);
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| 232 | x = tan(x);
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| 233 |
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| 234 | return mrb_float_value(mrb, x);
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| 235 | }
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| 236 |
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| 237 | /*
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| 238 | INVERSE TRIGONOMETRIC FUNCTIONS
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| 239 | */
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| 240 |
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| 241 | /*
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| 242 | * call-seq:
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| 243 | * Math.asin(x) -> float
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| 244 | *
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| 245 | * Computes the arc sine of <i>x</i>.
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| 246 | * @return computed value between `-(PI/2)` and `(PI/2)`.
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| 247 | */
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| 248 | static mrb_value
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| 249 | math_asin(mrb_state *mrb, mrb_value obj)
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| 250 | {
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| 251 | mrb_float x;
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| 252 |
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| 253 | mrb_get_args(mrb, "f", &x);
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| 254 | if (x < -1.0 || x > 1.0) {
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| 255 | domain_error(mrb, "asin");
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| 256 | }
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| 257 | x = asin(x);
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| 258 |
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| 259 | return mrb_float_value(mrb, x);
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| 260 | }
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| 261 |
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| 262 | /*
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| 263 | * call-seq:
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| 264 | * Math.acos(x) -> float
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| 265 | *
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| 266 | * Computes the arc cosine of <i>x</i>. Returns 0..PI.
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| 267 | */
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| 268 | static mrb_value
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| 269 | math_acos(mrb_state *mrb, mrb_value obj)
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| 270 | {
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| 271 | mrb_float x;
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| 272 |
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| 273 | mrb_get_args(mrb, "f", &x);
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| 274 | if (x < -1.0 || x > 1.0) {
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| 275 | domain_error(mrb, "acos");
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| 276 | }
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| 277 | x = acos(x);
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| 278 |
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| 279 | return mrb_float_value(mrb, x);
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| 280 | }
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| 281 |
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| 282 | /*
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| 283 | * call-seq:
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| 284 | * Math.atan(x) -> float
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| 285 | *
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| 286 | * Computes the arc tangent of <i>x</i>. Returns `-(PI/2) .. (PI/2)`.
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| 287 | */
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| 288 | static mrb_value
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| 289 | math_atan(mrb_state *mrb, mrb_value obj)
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| 290 | {
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| 291 | mrb_float x;
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| 292 |
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| 293 | mrb_get_args(mrb, "f", &x);
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| 294 | x = atan(x);
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| 295 |
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| 296 | return mrb_float_value(mrb, x);
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| 297 | }
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| 298 |
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| 299 | /*
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| 300 | * call-seq:
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| 301 | * Math.atan2(y, x) -> float
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| 302 | *
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| 303 | * Computes the arc tangent given <i>y</i> and <i>x</i>. Returns
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| 304 | * -PI..PI.
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| 305 | *
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| 306 | * Math.atan2(-0.0, -1.0) #=> -3.141592653589793
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| 307 | * Math.atan2(-1.0, -1.0) #=> -2.356194490192345
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| 308 | * Math.atan2(-1.0, 0.0) #=> -1.5707963267948966
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| 309 | * Math.atan2(-1.0, 1.0) #=> -0.7853981633974483
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| 310 | * Math.atan2(-0.0, 1.0) #=> -0.0
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| 311 | * Math.atan2(0.0, 1.0) #=> 0.0
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| 312 | * Math.atan2(1.0, 1.0) #=> 0.7853981633974483
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| 313 | * Math.atan2(1.0, 0.0) #=> 1.5707963267948966
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| 314 | * Math.atan2(1.0, -1.0) #=> 2.356194490192345
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| 315 | * Math.atan2(0.0, -1.0) #=> 3.141592653589793
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| 316 | *
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| 317 | */
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| 318 | static mrb_value
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| 319 | math_atan2(mrb_state *mrb, mrb_value obj)
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| 320 | {
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| 321 | mrb_float x, y;
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| 322 |
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| 323 | mrb_get_args(mrb, "ff", &x, &y);
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| 324 | x = atan2(x, y);
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| 325 |
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| 326 | return mrb_float_value(mrb, x);
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| 327 | }
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| 328 |
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| 329 |
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| 330 |
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| 331 | /*
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| 332 | HYPERBOLIC TRIG FUNCTIONS
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| 333 | */
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| 334 | /*
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| 335 | * call-seq:
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| 336 | * Math.sinh(x) -> float
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| 337 | *
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| 338 | * Computes the hyperbolic sine of <i>x</i> (expressed in
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| 339 | * radians).
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| 340 | */
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| 341 | static mrb_value
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| 342 | math_sinh(mrb_state *mrb, mrb_value obj)
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| 343 | {
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| 344 | mrb_float x;
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| 345 |
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| 346 | mrb_get_args(mrb, "f", &x);
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| 347 | x = sinh(x);
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| 348 |
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| 349 | return mrb_float_value(mrb, x);
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| 350 | }
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| 351 |
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| 352 | /*
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| 353 | * call-seq:
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| 354 | * Math.cosh(x) -> float
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| 355 | *
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| 356 | * Computes the hyperbolic cosine of <i>x</i> (expressed in radians).
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| 357 | */
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| 358 | static mrb_value
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| 359 | math_cosh(mrb_state *mrb, mrb_value obj)
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| 360 | {
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| 361 | mrb_float x;
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| 362 |
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| 363 | mrb_get_args(mrb, "f", &x);
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| 364 | x = cosh(x);
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| 365 |
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| 366 | return mrb_float_value(mrb, x);
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| 367 | }
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| 368 |
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| 369 | /*
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| 370 | * call-seq:
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| 371 | * Math.tanh() -> float
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| 372 | *
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| 373 | * Computes the hyperbolic tangent of <i>x</i> (expressed in
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| 374 | * radians).
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| 375 | */
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| 376 | static mrb_value
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| 377 | math_tanh(mrb_state *mrb, mrb_value obj)
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| 378 | {
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| 379 | mrb_float x;
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| 380 |
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| 381 | mrb_get_args(mrb, "f", &x);
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| 382 | x = tanh(x);
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| 383 |
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| 384 | return mrb_float_value(mrb, x);
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| 385 | }
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| 386 |
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| 387 |
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| 388 | /*
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| 389 | INVERSE HYPERBOLIC TRIG FUNCTIONS
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| 390 | */
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| 391 |
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| 392 | /*
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| 393 | * call-seq:
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| 394 | * Math.asinh(x) -> float
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| 395 | *
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| 396 | * Computes the inverse hyperbolic sine of <i>x</i>.
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| 397 | */
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| 398 | static mrb_value
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| 399 | math_asinh(mrb_state *mrb, mrb_value obj)
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| 400 | {
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| 401 | mrb_float x;
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| 402 |
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| 403 | mrb_get_args(mrb, "f", &x);
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| 404 |
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| 405 | x = asinh(x);
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| 406 |
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| 407 | return mrb_float_value(mrb, x);
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| 408 | }
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| 409 |
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| 410 | /*
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| 411 | * call-seq:
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| 412 | * Math.acosh(x) -> float
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| 413 | *
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| 414 | * Computes the inverse hyperbolic cosine of <i>x</i>.
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| 415 | */
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| 416 | static mrb_value
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| 417 | math_acosh(mrb_state *mrb, mrb_value obj)
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| 418 | {
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| 419 | mrb_float x;
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| 420 |
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| 421 | mrb_get_args(mrb, "f", &x);
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| 422 | if (x < 1.0) {
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| 423 | domain_error(mrb, "acosh");
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| 424 | }
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| 425 | x = acosh(x);
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| 426 |
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| 427 | return mrb_float_value(mrb, x);
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| 428 | }
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| 429 |
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| 430 | /*
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| 431 | * call-seq:
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| 432 | * Math.atanh(x) -> float
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| 433 | *
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| 434 | * Computes the inverse hyperbolic tangent of <i>x</i>.
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| 435 | */
|
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| 436 | static mrb_value
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| 437 | math_atanh(mrb_state *mrb, mrb_value obj)
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| 438 | {
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| 439 | mrb_float x;
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| 440 |
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| 441 | mrb_get_args(mrb, "f", &x);
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| 442 | if (x < -1.0 || x > 1.0) {
|
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| 443 | domain_error(mrb, "atanh");
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| 444 | }
|
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| 445 | x = atanh(x);
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| 446 |
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| 447 | return mrb_float_value(mrb, x);
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| 448 | }
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| 449 |
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| 450 | /*
|
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| 451 | EXPONENTIALS AND LOGARITHMS
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| 452 | */
|
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| 453 |
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| 454 | /*
|
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| 455 | * call-seq:
|
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| 456 | * Math.exp(x) -> float
|
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| 457 | *
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| 458 | * Returns e**x.
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| 459 | *
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| 460 | * Math.exp(0) #=> 1.0
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| 461 | * Math.exp(1) #=> 2.718281828459045
|
---|
| 462 | * Math.exp(1.5) #=> 4.4816890703380645
|
---|
| 463 | *
|
---|
| 464 | */
|
---|
| 465 | static mrb_value
|
---|
| 466 | math_exp(mrb_state *mrb, mrb_value obj)
|
---|
| 467 | {
|
---|
| 468 | mrb_float x;
|
---|
| 469 |
|
---|
| 470 | mrb_get_args(mrb, "f", &x);
|
---|
| 471 | x = exp(x);
|
---|
| 472 |
|
---|
| 473 | return mrb_float_value(mrb, x);
|
---|
| 474 | }
|
---|
| 475 |
|
---|
| 476 | /*
|
---|
| 477 | * call-seq:
|
---|
| 478 | * Math.log(numeric) -> float
|
---|
| 479 | * Math.log(num,base) -> float
|
---|
| 480 | *
|
---|
| 481 | * Returns the natural logarithm of <i>numeric</i>.
|
---|
| 482 | * If additional second argument is given, it will be the base
|
---|
| 483 | * of logarithm.
|
---|
| 484 | *
|
---|
| 485 | * Math.log(1) #=> 0.0
|
---|
| 486 | * Math.log(Math::E) #=> 1.0
|
---|
| 487 | * Math.log(Math::E**3) #=> 3.0
|
---|
| 488 | * Math.log(12,3) #=> 2.2618595071429146
|
---|
| 489 | *
|
---|
| 490 | */
|
---|
| 491 | static mrb_value
|
---|
| 492 | math_log(mrb_state *mrb, mrb_value obj)
|
---|
| 493 | {
|
---|
| 494 | mrb_float x, base;
|
---|
[439] | 495 | mrb_int argc;
|
---|
[270] | 496 |
|
---|
| 497 | argc = mrb_get_args(mrb, "f|f", &x, &base);
|
---|
| 498 | if (x < 0.0) {
|
---|
| 499 | domain_error(mrb, "log");
|
---|
| 500 | }
|
---|
| 501 | x = log(x);
|
---|
| 502 | if (argc == 2) {
|
---|
| 503 | if (base < 0.0) {
|
---|
| 504 | domain_error(mrb, "log");
|
---|
| 505 | }
|
---|
| 506 | x /= log(base);
|
---|
| 507 | }
|
---|
| 508 | return mrb_float_value(mrb, x);
|
---|
| 509 | }
|
---|
| 510 |
|
---|
| 511 | /*
|
---|
| 512 | * call-seq:
|
---|
| 513 | * Math.log2(numeric) -> float
|
---|
| 514 | *
|
---|
| 515 | * Returns the base 2 logarithm of <i>numeric</i>.
|
---|
| 516 | *
|
---|
| 517 | * Math.log2(1) #=> 0.0
|
---|
| 518 | * Math.log2(2) #=> 1.0
|
---|
| 519 | * Math.log2(32768) #=> 15.0
|
---|
| 520 | * Math.log2(65536) #=> 16.0
|
---|
| 521 | *
|
---|
| 522 | */
|
---|
| 523 | static mrb_value
|
---|
| 524 | math_log2(mrb_state *mrb, mrb_value obj)
|
---|
| 525 | {
|
---|
| 526 | mrb_float x;
|
---|
| 527 |
|
---|
| 528 | mrb_get_args(mrb, "f", &x);
|
---|
| 529 | if (x < 0.0) {
|
---|
| 530 | domain_error(mrb, "log2");
|
---|
| 531 | }
|
---|
| 532 | x = log2(x);
|
---|
| 533 |
|
---|
| 534 | return mrb_float_value(mrb, x);
|
---|
| 535 | }
|
---|
| 536 |
|
---|
| 537 | /*
|
---|
| 538 | * call-seq:
|
---|
| 539 | * Math.log10(numeric) -> float
|
---|
| 540 | *
|
---|
| 541 | * Returns the base 10 logarithm of <i>numeric</i>.
|
---|
| 542 | *
|
---|
| 543 | * Math.log10(1) #=> 0.0
|
---|
| 544 | * Math.log10(10) #=> 1.0
|
---|
| 545 | * Math.log10(10**100) #=> 100.0
|
---|
| 546 | *
|
---|
| 547 | */
|
---|
| 548 | static mrb_value
|
---|
| 549 | math_log10(mrb_state *mrb, mrb_value obj)
|
---|
| 550 | {
|
---|
| 551 | mrb_float x;
|
---|
| 552 |
|
---|
| 553 | mrb_get_args(mrb, "f", &x);
|
---|
| 554 | if (x < 0.0) {
|
---|
| 555 | domain_error(mrb, "log10");
|
---|
| 556 | }
|
---|
| 557 | x = log10(x);
|
---|
| 558 |
|
---|
| 559 | return mrb_float_value(mrb, x);
|
---|
| 560 | }
|
---|
| 561 |
|
---|
| 562 | /*
|
---|
| 563 | * call-seq:
|
---|
| 564 | * Math.sqrt(numeric) -> float
|
---|
| 565 | *
|
---|
| 566 | * Returns the square root of <i>numeric</i>.
|
---|
| 567 | *
|
---|
| 568 | */
|
---|
| 569 | static mrb_value
|
---|
| 570 | math_sqrt(mrb_state *mrb, mrb_value obj)
|
---|
| 571 | {
|
---|
| 572 | mrb_float x;
|
---|
| 573 |
|
---|
| 574 | mrb_get_args(mrb, "f", &x);
|
---|
| 575 | if (x < 0.0) {
|
---|
| 576 | domain_error(mrb, "sqrt");
|
---|
| 577 | }
|
---|
| 578 | x = sqrt(x);
|
---|
| 579 |
|
---|
| 580 | return mrb_float_value(mrb, x);
|
---|
| 581 | }
|
---|
| 582 |
|
---|
| 583 |
|
---|
| 584 | /*
|
---|
| 585 | * call-seq:
|
---|
| 586 | * Math.cbrt(numeric) -> float
|
---|
| 587 | *
|
---|
| 588 | * Returns the cube root of <i>numeric</i>.
|
---|
| 589 | *
|
---|
| 590 | * -9.upto(9) {|x|
|
---|
| 591 | * p [x, Math.cbrt(x), Math.cbrt(x)**3]
|
---|
| 592 | * }
|
---|
| 593 | * #=>
|
---|
| 594 | * [-9, -2.0800838230519, -9.0]
|
---|
| 595 | * [-8, -2.0, -8.0]
|
---|
| 596 | * [-7, -1.91293118277239, -7.0]
|
---|
| 597 | * [-6, -1.81712059283214, -6.0]
|
---|
| 598 | * [-5, -1.7099759466767, -5.0]
|
---|
| 599 | * [-4, -1.5874010519682, -4.0]
|
---|
| 600 | * [-3, -1.44224957030741, -3.0]
|
---|
| 601 | * [-2, -1.25992104989487, -2.0]
|
---|
| 602 | * [-1, -1.0, -1.0]
|
---|
| 603 | * [0, 0.0, 0.0]
|
---|
| 604 | * [1, 1.0, 1.0]
|
---|
| 605 | * [2, 1.25992104989487, 2.0]
|
---|
| 606 | * [3, 1.44224957030741, 3.0]
|
---|
| 607 | * [4, 1.5874010519682, 4.0]
|
---|
| 608 | * [5, 1.7099759466767, 5.0]
|
---|
| 609 | * [6, 1.81712059283214, 6.0]
|
---|
| 610 | * [7, 1.91293118277239, 7.0]
|
---|
| 611 | * [8, 2.0, 8.0]
|
---|
| 612 | * [9, 2.0800838230519, 9.0]
|
---|
| 613 | *
|
---|
| 614 | */
|
---|
| 615 | static mrb_value
|
---|
| 616 | math_cbrt(mrb_state *mrb, mrb_value obj)
|
---|
| 617 | {
|
---|
| 618 | mrb_float x;
|
---|
| 619 |
|
---|
| 620 | mrb_get_args(mrb, "f", &x);
|
---|
| 621 | x = cbrt(x);
|
---|
| 622 |
|
---|
| 623 | return mrb_float_value(mrb, x);
|
---|
| 624 | }
|
---|
| 625 |
|
---|
| 626 |
|
---|
| 627 | /*
|
---|
| 628 | * call-seq:
|
---|
| 629 | * Math.frexp(numeric) -> [ fraction, exponent ]
|
---|
| 630 | *
|
---|
| 631 | * Returns a two-element array containing the normalized fraction (a
|
---|
| 632 | * <code>Float</code>) and exponent (a <code>Fixnum</code>) of
|
---|
| 633 | * <i>numeric</i>.
|
---|
| 634 | *
|
---|
| 635 | * fraction, exponent = Math.frexp(1234) #=> [0.6025390625, 11]
|
---|
| 636 | * fraction * 2**exponent #=> 1234.0
|
---|
| 637 | */
|
---|
| 638 | static mrb_value
|
---|
| 639 | math_frexp(mrb_state *mrb, mrb_value obj)
|
---|
| 640 | {
|
---|
| 641 | mrb_float x;
|
---|
| 642 | int exp;
|
---|
| 643 |
|
---|
| 644 | mrb_get_args(mrb, "f", &x);
|
---|
| 645 | x = frexp(x, &exp);
|
---|
| 646 |
|
---|
| 647 | return mrb_assoc_new(mrb, mrb_float_value(mrb, x), mrb_fixnum_value(exp));
|
---|
| 648 | }
|
---|
| 649 |
|
---|
| 650 | /*
|
---|
| 651 | * call-seq:
|
---|
| 652 | * Math.ldexp(flt, int) -> float
|
---|
| 653 | *
|
---|
| 654 | * Returns the value of <i>flt</i>*(2**<i>int</i>).
|
---|
| 655 | *
|
---|
| 656 | * fraction, exponent = Math.frexp(1234)
|
---|
| 657 | * Math.ldexp(fraction, exponent) #=> 1234.0
|
---|
| 658 | */
|
---|
| 659 | static mrb_value
|
---|
| 660 | math_ldexp(mrb_state *mrb, mrb_value obj)
|
---|
| 661 | {
|
---|
| 662 | mrb_float x;
|
---|
| 663 | mrb_int i;
|
---|
| 664 |
|
---|
| 665 | mrb_get_args(mrb, "fi", &x, &i);
|
---|
[439] | 666 | x = ldexp(x, (int)i);
|
---|
[270] | 667 |
|
---|
| 668 | return mrb_float_value(mrb, x);
|
---|
| 669 | }
|
---|
| 670 |
|
---|
| 671 | /*
|
---|
| 672 | * call-seq:
|
---|
| 673 | * Math.hypot(x, y) -> float
|
---|
| 674 | *
|
---|
| 675 | * Returns sqrt(x**2 + y**2), the hypotenuse of a right-angled triangle
|
---|
| 676 | * with sides <i>x</i> and <i>y</i>.
|
---|
| 677 | *
|
---|
| 678 | * Math.hypot(3, 4) #=> 5.0
|
---|
| 679 | */
|
---|
| 680 | static mrb_value
|
---|
| 681 | math_hypot(mrb_state *mrb, mrb_value obj)
|
---|
| 682 | {
|
---|
| 683 | mrb_float x, y;
|
---|
| 684 |
|
---|
| 685 | mrb_get_args(mrb, "ff", &x, &y);
|
---|
| 686 | x = hypot(x, y);
|
---|
| 687 |
|
---|
| 688 | return mrb_float_value(mrb, x);
|
---|
| 689 | }
|
---|
| 690 |
|
---|
| 691 | /*
|
---|
| 692 | * call-seq:
|
---|
| 693 | * Math.erf(x) -> float
|
---|
| 694 | *
|
---|
| 695 | * Calculates the error function of x.
|
---|
| 696 | */
|
---|
| 697 | static mrb_value
|
---|
| 698 | math_erf(mrb_state *mrb, mrb_value obj)
|
---|
| 699 | {
|
---|
| 700 | mrb_float x;
|
---|
| 701 |
|
---|
| 702 | mrb_get_args(mrb, "f", &x);
|
---|
| 703 | x = erf(x);
|
---|
| 704 |
|
---|
| 705 | return mrb_float_value(mrb, x);
|
---|
| 706 | }
|
---|
| 707 |
|
---|
| 708 |
|
---|
| 709 | /*
|
---|
| 710 | * call-seq:
|
---|
| 711 | * Math.erfc(x) -> float
|
---|
| 712 | *
|
---|
| 713 | * Calculates the complementary error function of x.
|
---|
| 714 | */
|
---|
| 715 | static mrb_value
|
---|
| 716 | math_erfc(mrb_state *mrb, mrb_value obj)
|
---|
| 717 | {
|
---|
| 718 | mrb_float x;
|
---|
| 719 |
|
---|
| 720 | mrb_get_args(mrb, "f", &x);
|
---|
| 721 | x = erfc(x);
|
---|
| 722 |
|
---|
| 723 | return mrb_float_value(mrb, x);
|
---|
| 724 | }
|
---|
| 725 |
|
---|
| 726 | /* ------------------------------------------------------------------------*/
|
---|
| 727 | void
|
---|
| 728 | mrb_mruby_math_gem_init(mrb_state* mrb)
|
---|
| 729 | {
|
---|
| 730 | struct RClass *mrb_math;
|
---|
| 731 | mrb_math = mrb_define_module(mrb, "Math");
|
---|
| 732 |
|
---|
| 733 | mrb_define_class_under(mrb, mrb_math, "DomainError", mrb->eStandardError_class);
|
---|
| 734 |
|
---|
| 735 | #ifdef M_PI
|
---|
| 736 | mrb_define_const(mrb, mrb_math, "PI", mrb_float_value(mrb, M_PI));
|
---|
| 737 | #else
|
---|
| 738 | mrb_define_const(mrb, mrb_math, "PI", mrb_float_value(mrb, atan(1.0)*4.0));
|
---|
| 739 | #endif
|
---|
| 740 |
|
---|
| 741 | #ifdef M_E
|
---|
| 742 | mrb_define_const(mrb, mrb_math, "E", mrb_float_value(mrb, M_E));
|
---|
| 743 | #else
|
---|
| 744 | mrb_define_const(mrb, mrb_math, "E", mrb_float_value(mrb, exp(1.0)));
|
---|
| 745 | #endif
|
---|
| 746 |
|
---|
| 747 | mrb_define_module_function(mrb, mrb_math, "sin", math_sin, MRB_ARGS_REQ(1));
|
---|
| 748 | mrb_define_module_function(mrb, mrb_math, "cos", math_cos, MRB_ARGS_REQ(1));
|
---|
| 749 | mrb_define_module_function(mrb, mrb_math, "tan", math_tan, MRB_ARGS_REQ(1));
|
---|
| 750 |
|
---|
| 751 | mrb_define_module_function(mrb, mrb_math, "asin", math_asin, MRB_ARGS_REQ(1));
|
---|
| 752 | mrb_define_module_function(mrb, mrb_math, "acos", math_acos, MRB_ARGS_REQ(1));
|
---|
| 753 | mrb_define_module_function(mrb, mrb_math, "atan", math_atan, MRB_ARGS_REQ(1));
|
---|
| 754 | mrb_define_module_function(mrb, mrb_math, "atan2", math_atan2, MRB_ARGS_REQ(2));
|
---|
| 755 |
|
---|
| 756 | mrb_define_module_function(mrb, mrb_math, "sinh", math_sinh, MRB_ARGS_REQ(1));
|
---|
| 757 | mrb_define_module_function(mrb, mrb_math, "cosh", math_cosh, MRB_ARGS_REQ(1));
|
---|
| 758 | mrb_define_module_function(mrb, mrb_math, "tanh", math_tanh, MRB_ARGS_REQ(1));
|
---|
| 759 |
|
---|
| 760 | mrb_define_module_function(mrb, mrb_math, "asinh", math_asinh, MRB_ARGS_REQ(1));
|
---|
| 761 | mrb_define_module_function(mrb, mrb_math, "acosh", math_acosh, MRB_ARGS_REQ(1));
|
---|
| 762 | mrb_define_module_function(mrb, mrb_math, "atanh", math_atanh, MRB_ARGS_REQ(1));
|
---|
| 763 |
|
---|
| 764 | mrb_define_module_function(mrb, mrb_math, "exp", math_exp, MRB_ARGS_REQ(1));
|
---|
| 765 | mrb_define_module_function(mrb, mrb_math, "log", math_log, MRB_ARGS_REQ(1)|MRB_ARGS_OPT(1));
|
---|
| 766 | mrb_define_module_function(mrb, mrb_math, "log2", math_log2, MRB_ARGS_REQ(1));
|
---|
| 767 | mrb_define_module_function(mrb, mrb_math, "log10", math_log10, MRB_ARGS_REQ(1));
|
---|
| 768 | mrb_define_module_function(mrb, mrb_math, "sqrt", math_sqrt, MRB_ARGS_REQ(1));
|
---|
| 769 | mrb_define_module_function(mrb, mrb_math, "cbrt", math_cbrt, MRB_ARGS_REQ(1));
|
---|
| 770 |
|
---|
| 771 | mrb_define_module_function(mrb, mrb_math, "frexp", math_frexp, MRB_ARGS_REQ(1));
|
---|
| 772 | mrb_define_module_function(mrb, mrb_math, "ldexp", math_ldexp, MRB_ARGS_REQ(2));
|
---|
| 773 |
|
---|
| 774 | mrb_define_module_function(mrb, mrb_math, "hypot", math_hypot, MRB_ARGS_REQ(2));
|
---|
| 775 |
|
---|
| 776 | mrb_define_module_function(mrb, mrb_math, "erf", math_erf, MRB_ARGS_REQ(1));
|
---|
| 777 | mrb_define_module_function(mrb, mrb_math, "erfc", math_erfc, MRB_ARGS_REQ(1));
|
---|
| 778 | }
|
---|
| 779 |
|
---|
| 780 | void
|
---|
| 781 | mrb_mruby_math_gem_final(mrb_state* mrb)
|
---|
| 782 | {
|
---|
| 783 | }
|
---|