std::math

Status: experimental

Mathematical constants and f64 functions (Go's math package shape).

API details and source

The implementation source contains the complete declarations and implementation notes. The table below lists canonical Gossamer call signatures; every item name links directly to its implementation file.

Item	Canonical signature or declaration	Description
E	const E: f64	Euler's number e.
INF	const INF: f64	Positive infinity.
LN_10	const LN_10: f64	Natural log of 10.
LN_2	const LN_2: f64	Natural log of 2.
LOG10_E	const LOG10_E: f64	Base-10 logarithm of e.
LOG2_E	const LOG2_E: f64	Base-2 logarithm of e.
MAX_F64	const MAX_F64: f64	Largest finite f64 value.
MIN_POSITIVE_F64	const MIN_POSITIVE_F64: f64	Smallest positive normal f64 value.
NAN	const NAN: f64	Not-a-number value.
NEG_INF	const NEG_INF: f64	Negative infinity.
PHI	const PHI: f64	Golden ratio φ.
PI	const PI: f64	Archimedes' constant π.
SQRT_2	const SQRT_2: f64	√2.
abs	fn abs(x: f64) -> f64	Absolute value of x.
acos	fn acos(x: f64) -> f64	Arccosine (radians).
asin	fn asin(x: f64) -> f64	Arcsine (radians).
atan	fn atan(x: f64) -> f64	Arctangent (radians).
atan2	fn atan2(y: f64, x: f64) -> f64	Four-quadrant arctangent of y/x.
Int	type Int	Arbitrary-precision signed integer.
Uint	type Uint	Arbitrary-precision unsigned integer.
factorial	fn factorial(n: i64) -> big::Uint	Computes n! as an Int.
int_abs	fn int_abs(value: big::Int) -> big::Int	Absolute value of an Int.
int_add	fn int_add(a: big::Int, b: big::Int) -> big::Int	Sum of two Ints.
int_cmp	fn int_cmp(a: big::Int, b: big::Int) -> i64	Three-way comparison of two Ints (-1, 0, 1).
int_div	fn int_div(a: big::Int, b: big::Int) -> big::Int	Truncated quotient of two Ints.
int_from_i64	fn int_from_i64(value: i64) -> big::Int	Converts an i64 into an Int.
int_from_str	fn int_from_str(text: String) -> Result<big::Int, errors::Error>	Parses a decimal string into an Int.
int_gcd	fn int_gcd(a: big::Int, b: big::Int) -> big::Int	Greatest common divisor of two Ints.
int_is_negative	fn int_is_negative(value: big::Int) -> bool	Reports whether the Int is less than zero.
int_is_positive	fn int_is_positive(value: big::Int) -> bool	Reports whether the Int is greater than zero.
int_is_zero	fn int_is_zero(value: big::Int) -> bool	Reports whether the Int is zero.
int_lcm	fn int_lcm(a: big::Int, b: big::Int) -> big::Int	Least common multiple of two Ints.
int_mul	fn int_mul(a: big::Int, b: big::Int) -> big::Int	Product of two Ints.
int_neg	fn int_neg(value: big::Int) -> big::Int	Negation of an Int.
int_pow	fn int_pow(value: big::Int, exp: i64) -> big::Int	Int raised to a non-negative power.
int_rem	fn int_rem(a: big::Int, b: big::Int) -> big::Int	Remainder of two Ints.
int_sub	fn int_sub(a: big::Int, b: big::Int) -> big::Int	Difference of two Ints.
int_to_hex	fn int_to_hex(value: big::Int) -> String	Hexadecimal string form of an Int.
int_to_i64	fn int_to_i64(value: big::Int) -> Result<i64, errors::Error>	Narrows an Int to i64 where it fits.
int_to_str	fn int_to_str(value: big::Int) -> String	Decimal string form of an Int.
uint_add	fn uint_add(a: big::Uint, b: big::Uint) -> big::Uint	Sum of two Uints.
uint_bit_len	fn uint_bit_len(value: big::Uint) -> i64	Number of significant bits in a Uint.
uint_from_str	fn uint_from_str(text: String) -> Result<big::Uint, errors::Error>	Parses a decimal string into a Uint.
uint_from_u64	fn uint_from_u64(value: u64) -> big::Uint	Converts a u64 into a Uint.
uint_is_zero	fn uint_is_zero(value: big::Uint) -> bool	Reports whether the Uint is zero.
uint_mul	fn uint_mul(a: big::Uint, b: big::Uint) -> big::Uint	Product of two Uints.
uint_pow	fn uint_pow(value: big::Uint, exp: i64) -> big::Uint	Uint raised to a non-negative power.
uint_pow_mod	fn uint_pow_mod(value: big::Uint, exp: big::Uint, modulus: big::Uint) -> big::Uint	Modular exponentiation of a Uint.
uint_to_hex	fn uint_to_hex(value: big::Uint) -> String	Hexadecimal string form of a Uint.
uint_to_str	fn uint_to_str(value: big::Uint) -> String	Decimal string form of a Uint.
uint_to_u64	fn uint_to_u64(value: big::Uint) -> Result<u64, errors::Error>	Narrows a Uint to u64 where it fits.
add	fn add(x: u64, y: u64, carry: u64) -> (u64, u64)	x + y + carry; returns (sum, carry_out).
count_ones	fn count_ones(x: u64) -> i64	Number of set bits (popcount).
count_zeros	fn count_zeros(x: u64) -> i64	Number of clear bits.
div	fn div(hi: u64, lo: u64, y: u64) -> (u64, u64)	128-bit dividend / 64-bit divisor; returns (quotient, remainder).
leading_zeros	fn leading_zeros(x: u64) -> i64	Leading zero bit count.
len	fn len(x: u64) -> i64	Minimum bits required to represent x.
mul	fn mul(x: u64, y: u64) -> (u64, u64)	Full 128-bit product; returns (hi, lo).
reverse_bits	fn reverse_bits(x: u64) -> i64	Reverses bit order of x.
reverse_bytes	fn reverse_bytes(x: u64) -> i64	Reverses byte order of x.
rotate_left	fn rotate_left(x: u64, n: i64) -> u64	Rotates x left by n bits.
rotate_right	fn rotate_right(x: u64, n: i64) -> u64	Rotates x right by n bits.
sub	fn sub(x: u64, y: u64, borrow: u64) -> (u64, u64)	x - y - borrow; returns (diff, borrow_out).
trailing_zeros	fn trailing_zeros(x: u64) -> i64	Trailing zero bit count.
cbrt	fn cbrt(x: f64) -> f64	Cube root.
ceil	fn ceil(x: f64) -> f64	Smallest integer ≥ x.
clamp	fn clamp(x: f64, min: f64, max: f64) -> f64	Constrain x to the inclusive range [lo, hi].
copysign	fn copysign(x: f64, y: f64) -> f64	Magnitude of x with sign of y.
cos	fn cos(x: f64) -> f64	Cosine (radians).
cosh	fn cosh(x: f64) -> f64	Hyperbolic cosine.
exp	fn exp(x: f64) -> f64	e^x.
exp2	fn exp2(x: f64) -> f64	2^x.
floor	fn floor(x: f64) -> f64	Largest integer ≤ x.
hypot	fn hypot(x: f64, y: f64) -> f64	Euclidean distance √(x²+y²).
is_inf	fn is_inf(x: f64, sign: i64) -> bool	Reports whether x is infinite.
is_nan	fn is_nan(x: f64) -> bool	Reports whether x is NaN.
ln	fn ln(x: f64) -> f64	Natural logarithm.
log	fn log(x: f64, y: f64) -> f64	Logarithm with given base.
log10	fn log10(x: f64) -> f64	Base-10 logarithm.
log2	fn log2(x: f64) -> f64	Base-2 logarithm.
max	fn max(x: f64, y: f64) -> f64	Greater of two values.
min	fn min(x: f64, y: f64) -> f64	Lesser of two values.
positive_diff	fn positive_diff(x: f64, y: f64) -> f64	max(x-y, 0).
pow	fn pow(x: f64, y: f64) -> f64	x raised to the power y.
Rng	type Rng	SplitMix64-based RNG.
rem	fn rem(x: f64, y: f64) -> f64	Floating-point remainder x%y.
round	fn round(x: f64) -> f64	Nearest integer, half away from zero.
sin	fn sin(x: f64) -> f64	Sine (radians).
sinh	fn sinh(x: f64) -> f64	Hyperbolic sine.
sqrt	fn sqrt(x: f64) -> f64	Square root.
tan	fn tan(x: f64) -> f64	Tangent (radians).
tanh	fn tanh(x: f64) -> f64	Hyperbolic tangent.
trunc	fn trunc(x: f64) -> f64	Integer part of x.