rust/src/libcore/f64.rs

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/*
Module: f64
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Floating point operations and constants for `f64`
*/
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// PORT
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import cmath::c_double::*;
import cmath::c_double_targ_consts::*;
type t = f64;
// These are not defined inside consts:: for consistency with
// the integer types
// PORT check per architecture
// FIXME obtain these in a different way
const radix: uint = 2u;
const mantissa_digits: uint = 53u;
const digits: uint = 15u;
const epsilon: f64 = 2.2204460492503131e-16_f64;
const min_value: f64 = 2.2250738585072014e-308_f64;
const max_value: f64 = 1.7976931348623157e+308_f64;
const min_exp: int = -1021;
const max_exp: int = 1024;
const min_10_exp: int = -307;
const max_10_exp: int = 308;
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/* Const: NaN */
const NaN: f64 = 0.0_f64/0.0_f64;
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/* Const: infinity */
const infinity: f64 = 1.0_f64/0.0_f64;
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/* Const: neg_infinity */
const neg_infinity: f64 = -1.0_f64/0.0_f64;
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/* Predicate: isNaN */
pure fn is_NaN(f: f64) -> bool { f != f }
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/* Function: add */
pure fn add(x: f64, y: f64) -> f64 { ret x + y; }
/* Function: sub */
pure fn sub(x: f64, y: f64) -> f64 { ret x - y; }
/* Function: mul */
pure fn mul(x: f64, y: f64) -> f64 { ret x * y; }
/* Function: div */
pure fn div(x: f64, y: f64) -> f64 { ret x / y; }
/* Function: rem */
pure fn rem(x: f64, y: f64) -> f64 { ret x % y; }
/* Predicate: lt */
pure fn lt(x: f64, y: f64) -> bool { ret x < y; }
/* Predicate: le */
pure fn le(x: f64, y: f64) -> bool { ret x <= y; }
/* Predicate: eq */
pure fn eq(x: f64, y: f64) -> bool { ret x == y; }
/* Predicate: ne */
pure fn ne(x: f64, y: f64) -> bool { ret x != y; }
/* Predicate: ge */
pure fn ge(x: f64, y: f64) -> bool { ret x >= y; }
/* Predicate: gt */
pure fn gt(x: f64, y: f64) -> bool { ret x > y; }
/*
Predicate: is_positive
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Returns true if `x` is a positive number, including +0.0f640 and +Infinity.
*/
pure fn is_positive(x: f64) -> bool
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{ ret x > 0.0f64 || (1.0f64/x) == infinity; }
/*
Predicate: is_negative
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Returns true if `x` is a negative number, including -0.0f640 and -Infinity.
*/
pure fn is_negative(x: f64) -> bool
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{ ret x < 0.0f64 || (1.0f64/x) == neg_infinity; }
/*
Predicate: is_nonpositive
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Returns true if `x` is a negative number, including -0.0f640 and -Infinity.
(This is the same as `f64::negative`.)
*/
pure fn is_nonpositive(x: f64) -> bool {
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ret x < 0.0f64 || (1.0f64/x) == neg_infinity;
}
/*
Predicate: is_nonnegative
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Returns true if `x` is a positive number, including +0.0f640 and +Infinity.
(This is the same as `f64::positive`.)
*/
pure fn is_nonnegative(x: f64) -> bool {
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ret x > 0.0f64 || (1.0f64/x) == infinity;
}
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/*
Predicate: is_zero
Returns true if `x` is a zero number (positive or negative zero)
*/
pure fn is_zero(x: f64) -> bool {
ret x == 0.0f64 || x == -0.0f64;
}
/*
Predicate: is_infinite
Returns true if `x`is an infinite numer
*/
pure fn is_infinite(x: f64) -> bool {
ret x == infinity || x == neg_infinity;
}
/*
Predicate: is_finite
Returns true if `x`is a finite numer
*/
pure fn is_finite(x: f64) -> bool {
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ret !(is_NaN(x) || is_infinite(x));
}
// FIXME add is_normal, is_subnormal, and fpclassify
/* Module: consts */
mod consts {
// FIXME replace with mathematical constants from cmath
/*
Const: pi
Archimedes' constant
*/
const pi: f64 = 3.14159265358979323846264338327950288_f64;
/*
Const: frac_pi_2
pi/2.0
*/
const frac_pi_2: f64 = 1.57079632679489661923132169163975144_f64;
/*
Const: frac_pi_4
pi/4.0
*/
const frac_pi_4: f64 = 0.785398163397448309615660845819875721_f64;
/*
Const: frac_1_pi
1.0/pi
*/
const frac_1_pi: f64 = 0.318309886183790671537767526745028724_f64;
/*
Const: frac_2_pi
2.0/pi
*/
const frac_2_pi: f64 = 0.636619772367581343075535053490057448_f64;
/*
Const: frac_2_sqrtpi
2.0/sqrt(pi)
*/
const frac_2_sqrtpi: f64 = 1.12837916709551257389615890312154517_f64;
/*
Const: sqrt2
sqrt(2.0)
*/
const sqrt2: f64 = 1.41421356237309504880168872420969808_f64;
/*
Const: frac_1_sqrt2
1.0/sqrt(2.0)
*/
const frac_1_sqrt2: f64 = 0.707106781186547524400844362104849039_f64;
/*
Const: e
Euler's number
*/
const e: f64 = 2.71828182845904523536028747135266250_f64;
/*
Const: log2_e
log2(e)
*/
const log2_e: f64 = 1.44269504088896340735992468100189214_f64;
/*
Const: log10_e
log10(e)
*/
const log10_e: f64 = 0.434294481903251827651128918916605082_f64;
/*
Const: ln_2
ln(2.0)
*/
const ln_2: f64 = 0.693147180559945309417232121458176568_f64;
/*
Const: ln_10
ln(10.0)
*/
const ln_10: f64 = 2.30258509299404568401799145468436421_f64;
}
#[cfg(target_os="linux")]
#[cfg(target_os="macos")]
#[cfg(target_os="win32")]
pure fn logarithm(n: f64, b: f64) -> f64 {
ret log2(n) / log2(b);
}
#[cfg(target_os="freebsd")]
pure fn logarithm(n: f64, b: f64) -> f64 {
ret ln(n) / ln(b);
}
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#[cfg(target_os="freebsd")]
pure fn log2(n: f64) -> f64 {
ret ln(n) / consts::ln_2;
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}
//
// Local Variables:
// mode: rust
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End:
//