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Module std::uq32_32

Defines an unsigned, fixed-point numeric type with a 32-bit integer part and a 32-bit fractional part. The notation uq32_32 and UQ32_32 is based on Q notation. q indicates it a fixed-point number. The u prefix indicates it is unsigned. The 32_32 suffix indicates the number of bits, where the first number indicates the number of bits in the integer part, and the second the number of bits in the fractional part--in this case 32 bits for each.

Struct UQ32_32​

A fixed-point numeric type with 32 integer bits and 32 fractional bits, represented by an underlying 64 bit value. This is a binary representation, so decimal values may not be exactly representable, but it provides more than 9 decimal digits of precision both before and after the decimal point (18 digits total).

public struct UQ32_32 has copy, drop, store
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Fields
0: u64

Constants​

#[error]
const EDenominator: vector<u8> = b"Quotient specified with a zero denominator";

#[error]
const EQuotientTooSmall: vector<u8> = b"Quotient specified is too small, and is outside of the supported range";

#[error]
const EQuotientTooLarge: vector<u8> = b"Quotient specified is too large, and is outside of the supported range";

#[error]
const EOverflow: vector<u8> = b"Overflow from an arithmetic operation";

#[error]
const EDivisionByZero: vector<u8> = b"Division by zero";

The total number of bits in the fixed-point number. Used in macro invocations.

const TOTAL_BITS: u8 = 64;

The number of fractional bits in the fixed-point number. Used in macro invocations.

const FRACTIONAL_BITS: u8 = 32;

Function from_quotient​

Create a fixed-point value from a quotient specified by its numerator and denominator. from_quotient and from_int should be preferred over using from_raw. Unless the denominator is a power of two, fractions can not be represented accurately, so be careful about rounding errors.
Aborts if the denominator is zero.
Aborts if the input is non-zero but so small that it will be represented as zero, e.g. smaller than 2^{-32}.
Aborts if the input is too large, e.g. larger than or equal to 2^32.

public fun from_quotient(numerator: u64, denominator: u64): std::uq32_32::UQ32_32

Function from_int​

Create a fixed-point value from an integer. from_int and from_quotient should be preferred over using from_raw.

public fun from_int(integer: u32): std::uq32_32::UQ32_32

Function add​

Add two fixed-point numbers, a + b.
Aborts if the sum overflows.

Function sub​

Subtract two fixed-point numbers, a - b.
Aborts if a < b.

Function mul​

Multiply two fixed-point numbers, truncating any fractional part of the product.
Aborts if the product overflows.

Function div​

Divide two fixed-point numbers, truncating any fractional part of the quotient.
Aborts if the divisor is zero.
Aborts if the quotient overflows.

Function to_int​

Convert a fixed-point number to an integer, truncating any fractional part.

Function int_mul​

Multiply a u64 integer by a fixed-point number, truncating any fractional part of the product.
Aborts if the product overflows.

public fun int_mul(val: u64, multiplier: std::uq32_32::UQ32_32): u64

Function int_div​

Divide a u64 integer by a fixed-point number, truncating any fractional part of the quotient.
Aborts if the divisor is zero.
Aborts if the quotient overflows.

public fun int_div(val: u64, divisor: std::uq32_32::UQ32_32): u64

Function le​

Less than or equal to. Returns true if and only if a <= b.

Function lt​

Less than. Returns true if and only if a < b.

Function ge​

Greater than or equal to. Returns true if and only if a >= b.

Function gt​

Greater than. Returns true if and only if a > b.

Function to_raw​

Accessor for the raw u64 value. Can be paired with from_raw to perform less common operations on the raw values directly.

Function from_raw​

Accessor for the raw u64 value. Can be paired with to_raw to perform less common operations on the raw values directly.

public fun from_raw(raw_value: u64): std::uq32_32::UQ32_32