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			715 lines
		
	
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			715 lines
		
	
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/**********************************************************************
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  math.c -
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  $Author$
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  created at: Tue Jan 25 14:12:56 JST 1994
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  Copyright (C) 1993-2007 Yukihiro Matsumoto
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**********************************************************************/
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#include "ruby/ruby.h"
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#include <math.h>
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#include <errno.h>
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VALUE rb_mMath;
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static VALUE
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to_flo(VALUE x)
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{
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    if (!rb_obj_is_kind_of(x, rb_cNumeric)) {
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	rb_raise(rb_eTypeError, "can't convert %s into Float",
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		 NIL_P(x) ? "nil" :
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		 x == Qtrue ? "true" :
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		 x == Qfalse ? "false" :
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		 rb_obj_classname(x));
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    }
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    return rb_convert_type(x, T_FLOAT, "Float", "to_f");
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}
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#define Need_Float(x) (x) = to_flo(x)
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#define Need_Float2(x,y) do {\
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    Need_Float(x);\
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    Need_Float(y);\
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} while (0)
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static void
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domain_check(double x, const char *msg)
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{
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    while(1) {
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	if (errno) {
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	    rb_sys_fail(msg);
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	}
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	if (isnan(x)) {
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#if defined(EDOM)
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	    errno = EDOM;
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#elif defined(ERANGE)
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	    errno = ERANGE;
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#endif
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	    continue;
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	}
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	break;
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    }
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}
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static void
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infinity_check(VALUE arg, double res, const char *msg)
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{
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    while(1) {
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	if (errno) {
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	    rb_sys_fail(msg);
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	}
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	if (isinf(res) && !isinf(RFLOAT_VALUE(arg))) {
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#if defined(EDOM)
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	    errno = EDOM;
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#elif defined(ERANGE)
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	    errno = ERANGE;
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#endif
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	    continue;
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	}
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	break;
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    }
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}
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/*
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 *  call-seq:
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 *     Math.atan2(y, x)  => float
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 *  
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 *  Computes the arc tangent given <i>y</i> and <i>x</i>. Returns
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 *  -PI..PI.
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 *     
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 */
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VALUE
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math_atan2(VALUE obj, VALUE y, VALUE x)
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{
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    Need_Float2(y, x);
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    return DBL2NUM(atan2(RFLOAT_VALUE(y), RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.cos(x)    => float
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 *  
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 *  Computes the cosine of <i>x</i> (expressed in radians). Returns
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 *  -1..1.
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 */
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VALUE
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math_cos(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(cos(RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.sin(x)    => float
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 *  
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 *  Computes the sine of <i>x</i> (expressed in radians). Returns
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 *  -1..1.
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 */
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VALUE
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math_sin(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(sin(RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.tan(x)    => float
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 *  
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 *  Returns the tangent of <i>x</i> (expressed in radians).
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 */
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static VALUE
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math_tan(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(tan(RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.acos(x)    => float
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 *  
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 *  Computes the arc cosine of <i>x</i>. Returns 0..PI.
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 */
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static VALUE
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math_acos(VALUE obj, VALUE x)
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{
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    double d;
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    Need_Float(x);
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    errno = 0;
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    d = acos(RFLOAT_VALUE(x));
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    domain_check(d, "acos");
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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.asin(x)    => float
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 *  
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 *  Computes the arc sine of <i>x</i>. Returns -{PI/2} .. {PI/2}.
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 */
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static VALUE
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math_asin(VALUE obj, VALUE x)
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{
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    double d;
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    Need_Float(x);
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    errno = 0;
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    d = asin(RFLOAT_VALUE(x));
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    domain_check(d, "asin");
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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.atan(x)    => float
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 *  
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 *  Computes the arc tangent of <i>x</i>. Returns -{PI/2} .. {PI/2}.
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 */
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static VALUE
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math_atan(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(atan(RFLOAT_VALUE(x)));
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}
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#ifndef HAVE_COSH
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double
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cosh(double x)
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{
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    return (exp(x) + exp(-x)) / 2;
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}
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#endif
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/*
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 *  call-seq:
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 *     Math.cosh(x)    => float
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 *  
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 *  Computes the hyperbolic cosine of <i>x</i> (expressed in radians).
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 */
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VALUE
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math_cosh(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(cosh(RFLOAT_VALUE(x)));
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}
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#ifndef HAVE_SINH
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double
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sinh(double x)
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{
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    return (exp(x) - exp(-x)) / 2;
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}
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#endif
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/*
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 *  call-seq:
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 *     Math.sinh(x)    => float
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 *  
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 *  Computes the hyperbolic sine of <i>x</i> (expressed in
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 *  radians).
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 */
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VALUE
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math_sinh(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(sinh(RFLOAT_VALUE(x)));
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}
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#ifndef HAVE_TANH
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double
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tanh(double x)
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{
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    return sinh(x) / cosh(x);
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}
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#endif
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/*
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 *  call-seq:
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 *     Math.tanh()    => float
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 *  
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 *  Computes the hyperbolic tangent of <i>x</i> (expressed in
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 *  radians).
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 */
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static VALUE
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math_tanh(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(tanh(RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.acosh(x)    => float
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 *  
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 *  Computes the inverse hyperbolic cosine of <i>x</i>.
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 */
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static VALUE
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math_acosh(VALUE obj, VALUE x)
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{
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    double d;
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    Need_Float(x);
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    errno = 0;
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    d = acosh(RFLOAT_VALUE(x));
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    domain_check(d, "acosh");
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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.asinh(x)    => float
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 *  
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 *  Computes the inverse hyperbolic sine of <i>x</i>.
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 */
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static VALUE
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math_asinh(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(asinh(RFLOAT_VALUE(x)));
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}
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/*
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 *  call-seq:
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 *     Math.atanh(x)    => float
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 *  
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 *  Computes the inverse hyperbolic tangent of <i>x</i>.
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 */
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static VALUE
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math_atanh(VALUE obj, VALUE x)
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{
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    double d;
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    Need_Float(x);
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    errno = 0;
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    d = atanh(RFLOAT_VALUE(x));
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    domain_check(d, "atanh");
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    infinity_check(x, d, "atanh");
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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.exp(x)    => float
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 *  
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 *  Returns e**x.
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 */
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VALUE
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math_exp(VALUE obj, VALUE x)
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{
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    Need_Float(x);
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    return DBL2NUM(exp(RFLOAT_VALUE(x)));
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}
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#if defined __CYGWIN__
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# include <cygwin/version.h>
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# if CYGWIN_VERSION_DLL_MAJOR < 1005
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#  define nan(x) nan()
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# endif
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# define log(x) ((x) < 0.0 ? nan("") : log(x))
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# define log10(x) ((x) < 0.0 ? nan("") : log10(x))
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#endif
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/*
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 *  call-seq:
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 *     Math.log(numeric)    => float
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 *     Math.log(num,base)   => float
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 *  
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 *  Returns the natural logarithm of <i>numeric</i>.
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 *  If additional second argument is given, it will be the base
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 *  of logarithm.
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 */
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VALUE
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math_log(int argc, VALUE *argv)
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{
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    VALUE x, base;
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    double d;
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    rb_scan_args(argc, argv, "11", &x, &base);
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    Need_Float(x);
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    errno = 0;
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    d = log(RFLOAT_VALUE(x));
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    if (argc == 2) {
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	Need_Float(base);
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	d /= log(RFLOAT_VALUE(base));
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    }
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    domain_check(d, "log");
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    infinity_check(x, d, "log");
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    return DBL2NUM(d);
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}
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#ifndef log2
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#ifndef HAVE_LOG2
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double
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log2(double x)
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{
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    return log10(x)/log10(2.0);
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}
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#else
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extern double log2(double);
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#endif
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#endif
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/*
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 *  call-seq:
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 *     Math.log2(numeric)    => float
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 *  
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 *  Returns the base 2 logarithm of <i>numeric</i>.
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 */
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static VALUE
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math_log2(VALUE obj, VALUE x)
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{
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    double d;
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    Need_Float(x);
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    errno = 0;
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    d = log2(RFLOAT_VALUE(x));
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    domain_check(d, "log2");
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    infinity_check(x, d, "log2");
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    return DBL2NUM(d);
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}
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 | 
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/*
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 *  call-seq:
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 *     Math.log10(numeric)    => float
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 *  
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 *  Returns the base 10 logarithm of <i>numeric</i>.
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 */
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static VALUE
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math_log10(VALUE obj, VALUE x)
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{
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    double d;
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 | 
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    Need_Float(x);
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    errno = 0;
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    d = log10(RFLOAT_VALUE(x));
 | 
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    domain_check(d, "log10");
 | 
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    infinity_check(x, d, "log10");
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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.sqrt(numeric)    => float
 | 
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 *  
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 *  Returns the non-negative square root of <i>numeric</i>.
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 *
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 *    0.upto(10) {|x|            
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 *      p [x, Math.sqrt(x), Math.sqrt(x)**2]
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 *    }
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 *    #=>
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 *    [0, 0.0, 0.0]
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 *    [1, 1.0, 1.0]
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 *    [2, 1.4142135623731, 2.0]
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						|
 *    [3, 1.73205080756888, 3.0]
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						|
 *    [4, 2.0, 4.0]
 | 
						|
 *    [5, 2.23606797749979, 5.0]
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						|
 *    [6, 2.44948974278318, 6.0]
 | 
						|
 *    [7, 2.64575131106459, 7.0]
 | 
						|
 *    [8, 2.82842712474619, 8.0]
 | 
						|
 *    [9, 3.0, 9.0]
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						|
 *    [10, 3.16227766016838, 10.0]
 | 
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 *
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 */
 | 
						|
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VALUE
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						|
math_sqrt(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    double d;
 | 
						|
 | 
						|
    Need_Float(x);
 | 
						|
    errno = 0;
 | 
						|
    d = sqrt(RFLOAT_VALUE(x));
 | 
						|
    domain_check(d, "sqrt");
 | 
						|
    return DBL2NUM(d);
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  call-seq:
 | 
						|
 *     Math.cbrt(numeric)    => float
 | 
						|
 *  
 | 
						|
 *  Returns the cube root of <i>numeric</i>.
 | 
						|
 *
 | 
						|
 *    -9.upto(9) {|x|
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						|
 *      p [x, Math.cbrt(x), Math.cbrt(x)**3]
 | 
						|
 *    }
 | 
						|
 *    #=>
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						|
 *    [-9, -2.0800838230519, -9.0]
 | 
						|
 *    [-8, -2.0, -8.0]
 | 
						|
 *    [-7, -1.91293118277239, -7.0]
 | 
						|
 *    [-6, -1.81712059283214, -6.0]
 | 
						|
 *    [-5, -1.7099759466767, -5.0]
 | 
						|
 *    [-4, -1.5874010519682, -4.0]
 | 
						|
 *    [-3, -1.44224957030741, -3.0]
 | 
						|
 *    [-2, -1.25992104989487, -2.0]
 | 
						|
 *    [-1, -1.0, -1.0]
 | 
						|
 *    [0, 0.0, 0.0]
 | 
						|
 *    [1, 1.0, 1.0]
 | 
						|
 *    [2, 1.25992104989487, 2.0]
 | 
						|
 *    [3, 1.44224957030741, 3.0]
 | 
						|
 *    [4, 1.5874010519682, 4.0]
 | 
						|
 *    [5, 1.7099759466767, 5.0]
 | 
						|
 *    [6, 1.81712059283214, 6.0]
 | 
						|
 *    [7, 1.91293118277239, 7.0]
 | 
						|
 *    [8, 2.0, 8.0]
 | 
						|
 *    [9, 2.0800838230519, 9.0]
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
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math_cbrt(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    Need_Float(x);
 | 
						|
    return DBL2NUM(cbrt(RFLOAT_VALUE(x)));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  call-seq:
 | 
						|
 *     Math.frexp(numeric)    => [ fraction, exponent ]
 | 
						|
 *  
 | 
						|
 *  Returns a two-element array containing the normalized fraction (a
 | 
						|
 *  <code>Float</code>) and exponent (a <code>Fixnum</code>) of
 | 
						|
 *  <i>numeric</i>.
 | 
						|
 *     
 | 
						|
 *     fraction, exponent = Math.frexp(1234)   #=> [0.6025390625, 11]
 | 
						|
 *     fraction * 2**exponent                  #=> 1234.0
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_frexp(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    double d;
 | 
						|
    int exp;
 | 
						|
 | 
						|
    Need_Float(x);
 | 
						|
    
 | 
						|
    d = frexp(RFLOAT_VALUE(x), &exp);
 | 
						|
    return rb_assoc_new(DBL2NUM(d), INT2NUM(exp));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  call-seq:
 | 
						|
 *     Math.ldexp(flt, int) -> float
 | 
						|
 *  
 | 
						|
 *  Returns the value of <i>flt</i>*(2**<i>int</i>).
 | 
						|
 *     
 | 
						|
 *     fraction, exponent = Math.frexp(1234)
 | 
						|
 *     Math.ldexp(fraction, exponent)   #=> 1234.0
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_ldexp(VALUE obj, VALUE x, VALUE n)
 | 
						|
{
 | 
						|
    Need_Float(x);
 | 
						|
    return DBL2NUM(ldexp(RFLOAT_VALUE(x), NUM2INT(n)));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  call-seq:
 | 
						|
 *     Math.hypot(x, y)    => float
 | 
						|
 *  
 | 
						|
 *  Returns sqrt(x**2 + y**2), the hypotenuse of a right-angled triangle
 | 
						|
 *  with sides <i>x</i> and <i>y</i>.
 | 
						|
 *     
 | 
						|
 *     Math.hypot(3, 4)   #=> 5.0
 | 
						|
 */
 | 
						|
 | 
						|
VALUE
 | 
						|
math_hypot(VALUE obj, VALUE x, VALUE y)
 | 
						|
{
 | 
						|
    Need_Float2(x, y);
 | 
						|
    return DBL2NUM(hypot(RFLOAT_VALUE(x), RFLOAT_VALUE(y)));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * call-seq:
 | 
						|
 *    Math.erf(x)  => float
 | 
						|
 *
 | 
						|
 *  Calculates the error function of x.
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_erf(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    Need_Float(x);
 | 
						|
    return DBL2NUM(erf(RFLOAT_VALUE(x)));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * call-seq:
 | 
						|
 *    Math.erfc(x)  => float
 | 
						|
 *
 | 
						|
 *  Calculates the complementary error function of x.
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_erfc(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    Need_Float(x);
 | 
						|
    return DBL2NUM(erfc(RFLOAT_VALUE(x)));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * call-seq:
 | 
						|
 *    Math.gamma(x)  => float
 | 
						|
 *
 | 
						|
 *  Calculates the gamma function of x.
 | 
						|
 *
 | 
						|
 *  Note that gamma(n) is same as fact(n-1) for integer n >= 0.
 | 
						|
 *  However gamma(n) returns float and possibly has error in calculation.
 | 
						|
 *
 | 
						|
 *   def fact(n) (1..n).inject(1) {|r,i| r*i } end
 | 
						|
 *   0.upto(25) {|i| p [i, Math.gamma(i+1), fact(i)] }
 | 
						|
 *   #=>
 | 
						|
 *   [0, 1.0, 1]
 | 
						|
 *   [1, 1.0, 1]
 | 
						|
 *   [2, 2.0, 2]
 | 
						|
 *   [3, 6.0, 6]
 | 
						|
 *   [4, 24.0, 24]
 | 
						|
 *   [5, 120.0, 120]
 | 
						|
 *   [6, 720.0, 720]
 | 
						|
 *   [7, 5040.0, 5040]
 | 
						|
 *   [8, 40320.0, 40320]
 | 
						|
 *   [9, 362880.0, 362880]
 | 
						|
 *   [10, 3628800.0, 3628800]
 | 
						|
 *   [11, 39916800.0, 39916800]
 | 
						|
 *   [12, 479001599.999999, 479001600]
 | 
						|
 *   [13, 6227020800.00001, 6227020800]
 | 
						|
 *   [14, 87178291199.9998, 87178291200]
 | 
						|
 *   [15, 1307674368000.0, 1307674368000]
 | 
						|
 *   [16, 20922789888000.0, 20922789888000]
 | 
						|
 *   [17, 3.55687428096001e+14, 355687428096000]
 | 
						|
 *   [18, 6.40237370572799e+15, 6402373705728000]
 | 
						|
 *   [19, 1.21645100408832e+17, 121645100408832000]
 | 
						|
 *   [20, 2.43290200817664e+18, 2432902008176640000]
 | 
						|
 *   [21, 5.10909421717094e+19, 51090942171709440000]
 | 
						|
 *   [22, 1.12400072777761e+21, 1124000727777607680000]
 | 
						|
 *   [23, 2.58520167388851e+22, 25852016738884976640000]
 | 
						|
 *   [24, 6.20448401733239e+23, 620448401733239439360000]
 | 
						|
 *   [25, 1.5511210043331e+25, 15511210043330985984000000]
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_gamma(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    double d;
 | 
						|
    Need_Float(x);
 | 
						|
    errno = 0;
 | 
						|
    d = tgamma(RFLOAT_VALUE(x));
 | 
						|
    domain_check(d, "gamma");
 | 
						|
    return DBL2NUM(d);
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * call-seq:
 | 
						|
 *    Math.lgamma(x)  => [float, -1 or 1]
 | 
						|
 *
 | 
						|
 *  Calculates the logarithmic gamma of x and
 | 
						|
 *  the sign of gamma of x.
 | 
						|
 *
 | 
						|
 *  Math.lgamma(x) is same as
 | 
						|
 *   [Math.log(Math.gamma(x).abs), Math.gamma(x) < 0 ? -1 : 1]
 | 
						|
 *  but avoid overflow by Math.gamma(x) for large x.
 | 
						|
 */
 | 
						|
 | 
						|
static VALUE
 | 
						|
math_lgamma(VALUE obj, VALUE x)
 | 
						|
{
 | 
						|
    double d;
 | 
						|
    int sign;
 | 
						|
    VALUE v;
 | 
						|
    Need_Float(x);
 | 
						|
    errno = 0;
 | 
						|
    d = lgamma_r(RFLOAT_VALUE(x), &sign);
 | 
						|
    domain_check(d, "lgamma");
 | 
						|
    v = DBL2NUM(d);
 | 
						|
    return rb_assoc_new(v, INT2FIX(sign));
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 *  The <code>Math</code> module contains module functions for basic
 | 
						|
 *  trigonometric and transcendental functions. See class
 | 
						|
 *  <code>Float</code> for a list of constants that
 | 
						|
 *  define Ruby's floating point accuracy.
 | 
						|
 */     
 | 
						|
 | 
						|
 | 
						|
void
 | 
						|
Init_Math(void)
 | 
						|
{
 | 
						|
    rb_mMath = rb_define_module("Math");
 | 
						|
 | 
						|
#ifdef M_PI
 | 
						|
    rb_define_const(rb_mMath, "PI", DBL2NUM(M_PI));
 | 
						|
#else
 | 
						|
    rb_define_const(rb_mMath, "PI", DBL2NUM(atan(1.0)*4.0));
 | 
						|
#endif
 | 
						|
 | 
						|
#ifdef M_E
 | 
						|
    rb_define_const(rb_mMath, "E", DBL2NUM(M_E));
 | 
						|
#else
 | 
						|
    rb_define_const(rb_mMath, "E", DBL2NUM(exp(1.0)));
 | 
						|
#endif
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "atan2", math_atan2, 2);
 | 
						|
    rb_define_module_function(rb_mMath, "cos", math_cos, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "sin", math_sin, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "tan", math_tan, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "acos", math_acos, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "asin", math_asin, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "atan", math_atan, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "cosh", math_cosh, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "sinh", math_sinh, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "tanh", math_tanh, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "acosh", math_acosh, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "asinh", math_asinh, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "atanh", math_atanh, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "exp", math_exp, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "log", math_log, -1);
 | 
						|
    rb_define_module_function(rb_mMath, "log2", math_log2, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "log10", math_log10, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "sqrt", math_sqrt, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "cbrt", math_cbrt, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "frexp", math_frexp, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "ldexp", math_ldexp, 2);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "hypot", math_hypot, 2);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "erf",  math_erf,  1);
 | 
						|
    rb_define_module_function(rb_mMath, "erfc", math_erfc, 1);
 | 
						|
 | 
						|
    rb_define_module_function(rb_mMath, "gamma", math_gamma, 1);
 | 
						|
    rb_define_module_function(rb_mMath, "lgamma", math_lgamma, 1);
 | 
						|
}
 |