Feature #10225 ยป _ math.c New method Math.normcdf.PATCH
| math.c | ||
|---|---|---|
| 777 | 777 |
/* |
| 778 | 778 |
* call-seq: |
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* Math.normcdf(x) -> Float |
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| 780 |
* |
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* Calculates cumulative distribution function (CDF) of the standard normal distribution for +x+. |
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* |
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* Domain: (-INFINITY, INFINITY) |
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* |
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* Codomain: (0.0, 1.0) |
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* |
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* Math.normcdf(0) #=> 0.5 |
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* |
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*/ |
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static VALUE |
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math_normcdf(VALUE obj, VALUE x) |
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{
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double d0, d; |
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Need_Float(x); |
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d0 = RFLOAT_VALUE(x); |
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d = 0.5 * (1.0 + erf(d0 / sqrt(2))); |
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return DBL2NUM(d); |
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} |
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/* |
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* call-seq: |
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* Math.gamma(x) -> Float |
| 780 | 804 |
* |
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* Calculates the gamma function of x. |
| ... | ... | |
| 1010 | 1034 |
rb_define_module_function(rb_mMath, "erf", math_erf, 1); |
| 1011 | 1035 |
rb_define_module_function(rb_mMath, "erfc", math_erfc, 1); |
| 1036 |
rb_define_module_function(rb_mMath, "normcdf", math_normcdf, 1); |
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| 1037 | ||
| 1012 | 1038 |
rb_define_module_function(rb_mMath, "gamma", math_gamma, 1); |
| 1013 | 1039 |
rb_define_module_function(rb_mMath, "lgamma", math_lgamma, 1); |
| 1014 | 1040 |
} |