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