Struct rust_decimal::prelude::Decimal [−][src]
#[repr(C)]pub struct Decimal { /* fields omitted */ }
Expand description
Decimal
represents a 128 bit representation of a fixed-precision decimal number.
The finite set of values of type Decimal
are of the form m / 10e,
where m is an integer such that -296 < m < 296, and e is an integer
between 0 and 28 inclusive.
Implementations
A constant representing -1.
A constant representing 100.
A constant representing 1000.
A constant representing Euler’s number (e) as 2.7182818284590452353602874714
A constant representing the inverse of Euler’s number (1/e) as 0.3678794411714423215955237702
Returns a Decimal
with a 64 bit m
representation and corresponding e
scale.
Arguments
num
- An i64 that represents them
portion of the decimal numberscale
- A u32 representing thee
portion of the decimal number.
Panics
This function panics if scale
is > 28.
Example
use rust_decimal::Decimal; let pi = Decimal::new(3141, 3); assert_eq!(pi.to_string(), "3.141");
Checked version of Decimal::new
. Will return Err
instead of panicking at run-time.
Example
use rust_decimal::Decimal; let max = Decimal::try_new(i64::MAX, u32::MAX); assert!(max.is_err());
Creates a Decimal
using a 128 bit signed m
representation and corresponding e
scale.
Arguments
num
- An i128 that represents them
portion of the decimal numberscale
- A u32 representing thee
portion of the decimal number.
Panics
This function panics if scale
is > 28 or if num
exceeds the maximum supported 96 bits.
Example
use rust_decimal::Decimal; let pi = Decimal::from_i128_with_scale(3141i128, 3); assert_eq!(pi.to_string(), "3.141");
Checked version of Decimal::from_i128_with_scale
. Will return Err
instead
of panicking at run-time.
Example
use rust_decimal::Decimal; let max = Decimal::try_from_i128_with_scale(i128::MAX, u32::MAX); assert!(max.is_err());
Returns a Decimal
using the instances constituent parts.
Arguments
lo
- The low 32 bits of a 96-bit integer.mid
- The middle 32 bits of a 96-bit integer.hi
- The high 32 bits of a 96-bit integer.negative
-true
to indicate a negative number.scale
- A power of 10 ranging from 0 to 28.
Caution: Undefined behavior
While a scale greater than 28 can be passed in, it will be automatically capped by this function at the maximum precision. The library opts towards this functionality as opposed to a panic to ensure that the function can be treated as constant. This may lead to undefined behavior in downstream applications and should be treated with caution.
Example
use rust_decimal::Decimal; let pi = Decimal::from_parts(1102470952, 185874565, 1703060790, false, 28); assert_eq!(pi.to_string(), "3.1415926535897932384626433832");
Returns a Result
which if successful contains the Decimal
constitution of
the scientific notation provided by value
.
Arguments
value
- The scientific notation of theDecimal
.
Example
use rust_decimal::Decimal; let value = Decimal::from_scientific("9.7e-7").unwrap(); assert_eq!(value.to_string(), "0.00000097");
Returns the scale of the decimal number, otherwise known as e
.
Example
use rust_decimal::Decimal; let num = Decimal::new(1234, 3); assert_eq!(num.scale(), 3u32);
Returns the mantissa of the decimal number.
Example
use rust_decimal::prelude::*; let num = Decimal::from_str("-1.2345678").unwrap(); assert_eq!(num.mantissa(), -12345678i128); assert_eq!(num.scale(), 7);
Returns true if this Decimal number is equivalent to zero.
Example
use rust_decimal::prelude::*; let num = Decimal::ZERO; assert!(num.is_zero());
👎 Deprecated since 1.4.0: please use set_sign_positive
instead
please use set_sign_positive
instead
Modifies the Decimal
to the given scale, attempting to do so without changing the
underlying number itself.
Note that setting the scale to something less then the current Decimal
s scale will
cause the newly created Decimal
to have some rounding.
Scales greater than the maximum precision supported by Decimal
will be automatically
rounded to Decimal::MAX_PRECISION
.
Rounding leverages the half up strategy.
Arguments
scale
: The scale to use for the newDecimal
number.
Example
use rust_decimal::prelude::*; // Rescaling to a higher scale preserves the value let mut number = Decimal::from_str("1.123").unwrap(); assert_eq!(number.scale(), 3); number.rescale(6); assert_eq!(number.to_string(), "1.123000"); assert_eq!(number.scale(), 6); // Rescaling to a lower scale forces the number to be rounded let mut number = Decimal::from_str("1.45").unwrap(); assert_eq!(number.scale(), 2); number.rescale(1); assert_eq!(number.to_string(), "1.5"); assert_eq!(number.scale(), 1);
Returns a serialized version of the decimal number. The resulting byte array will have the following representation:
- Bytes 1-4: flags
- Bytes 5-8: lo portion of
m
- Bytes 9-12: mid portion of
m
- Bytes 13-16: high portion of
m
Deserializes the given bytes into a decimal number. The deserialized byte representation must be 16 bytes and adhere to the following convention:
- Bytes 1-4: flags
- Bytes 5-8: lo portion of
m
- Bytes 9-12: mid portion of
m
- Bytes 13-16: high portion of
m
👎 Deprecated since 0.6.3: please use is_sign_negative
instead
please use is_sign_negative
instead
Returns true
if the decimal is negative.
👎 Deprecated since 0.6.3: please use is_sign_positive
instead
please use is_sign_positive
instead
Returns true
if the decimal is positive.
Returns true
if the sign bit of the decimal is negative.
Returns true
if the sign bit of the decimal is positive.
👎 Deprecated since 1.12.0: Use the associated constant Decimal::MIN
Use the associated constant Decimal::MIN
Returns the minimum possible number that Decimal
can represent.
👎 Deprecated since 1.12.0: Use the associated constant Decimal::MAX
Use the associated constant Decimal::MAX
Returns the maximum possible number that Decimal
can represent.
Returns a new Decimal
integral with no fractional portion.
This is a true truncation whereby no rounding is performed.
Example
use rust_decimal::Decimal; let pi = Decimal::new(3141, 3); let trunc = Decimal::new(3, 0); // note that it returns a decimal assert_eq!(pi.trunc(), trunc);
Returns a new Decimal
representing the fractional portion of the number.
Example
use rust_decimal::Decimal; let pi = Decimal::new(3141, 3); let fract = Decimal::new(141, 3); // note that it returns a decimal assert_eq!(pi.fract(), fract);
Computes the absolute value of self
.
Example
use rust_decimal::Decimal; let num = Decimal::new(-3141, 3); assert_eq!(num.abs().to_string(), "3.141");
Returns the largest integer less than or equal to a number.
Example
use rust_decimal::Decimal; let num = Decimal::new(3641, 3); assert_eq!(num.floor().to_string(), "3");
Returns the smallest integer greater than or equal to a number.
Example
use rust_decimal::Decimal; let num = Decimal::new(3141, 3); assert_eq!(num.ceil().to_string(), "4"); let num = Decimal::new(3, 0); assert_eq!(num.ceil().to_string(), "3");
Returns the maximum of the two numbers.
use rust_decimal::Decimal; let x = Decimal::new(1, 0); let y = Decimal::new(2, 0); assert_eq!(y, x.max(y));
Returns the minimum of the two numbers.
use rust_decimal::Decimal; let x = Decimal::new(1, 0); let y = Decimal::new(2, 0); assert_eq!(x, x.min(y));
Strips any trailing zero’s from a Decimal
and converts -0 to 0.
Example
use rust_decimal::prelude::*; let number = Decimal::from_str("3.100").unwrap(); assert_eq!(number.normalize().to_string(), "3.1");
An in place version of normalize
. Strips any trailing zero’s from a Decimal
and converts -0 to 0.
Example
use rust_decimal::prelude::*; let mut number = Decimal::from_str("3.100").unwrap(); assert_eq!(number.to_string(), "3.100"); number.normalize_assign(); assert_eq!(number.to_string(), "3.1");
Returns a new Decimal
number with no fractional portion (i.e. an integer).
Rounding currently follows “Bankers Rounding” rules. e.g. 6.5 -> 6, 7.5 -> 8
Example
use rust_decimal::Decimal; // Demonstrating bankers rounding... let number_down = Decimal::new(65, 1); let number_up = Decimal::new(75, 1); assert_eq!(number_down.round().to_string(), "6"); assert_eq!(number_up.round().to_string(), "8");
Returns a new Decimal
number with the specified number of decimal points for fractional
portion.
Rounding is performed using the provided RoundingStrategy
Arguments
dp
: the number of decimal points to round to.strategy
: theRoundingStrategy
to use.
Example
use rust_decimal::{Decimal, RoundingStrategy}; use core::str::FromStr; let tax = Decimal::from_str("3.4395").unwrap(); assert_eq!(tax.round_dp_with_strategy(2, RoundingStrategy::MidpointAwayFromZero).to_string(), "3.44");
Returns a new Decimal
number with the specified number of decimal points for fractional portion.
Rounding currently follows “Bankers Rounding” rules. e.g. 6.5 -> 6, 7.5 -> 8
Arguments
dp
: the number of decimal points to round to.
Example
use rust_decimal::Decimal; use core::str::FromStr; let pi = Decimal::from_str("3.1415926535897932384626433832").unwrap(); assert_eq!(pi.round_dp(2).to_string(), "3.14");
Convert Decimal
to an internal representation of the underlying struct. This is useful
for debugging the internal state of the object.
Important Disclaimer
This is primarily intended for library maintainers. The internal representation of a
Decimal
is considered “unstable” for public use.
Example
use rust_decimal::Decimal; use core::str::FromStr; let pi = Decimal::from_str("3.1415926535897932384626433832").unwrap(); assert_eq!(format!("{:?}", pi), "3.1415926535897932384626433832"); assert_eq!(format!("{:?}", pi.unpack()), "UnpackedDecimal { \ negative: false, scale: 28, hi: 1703060790, mid: 185874565, lo: 1102470952 \ }");
Checked addition. Computes self + other
, returning None
if overflow occurred.
Checked subtraction. Computes self - other
, returning None
if overflow occurred.
Checked multiplication. Computes self * other
, returning None
if overflow occurred.
Checked division. Computes self / other
, returning None
if other == 0.0
or the
division results in overflow.
Checked remainder. Computes self % other
, returning None
if other == 0.0
.
Trait Implementations
Performs the +=
operation. Read more
Performs the +=
operation. Read more
Performs the +=
operation. Read more
Performs the +=
operation. Read more
type Expression = Bound<Nullable<Numeric>, Self>
type Expression = Bound<Nullable<Numeric>, Self>
The expression being returned
Perform the conversion
type Expression = Bound<Nullable<Numeric>, Self>
type Expression = Bound<Nullable<Numeric>, Self>
The expression being returned
Perform the conversion
type Expression = Bound<Numeric, Self>
type Expression = Bound<Numeric, Self>
The expression being returned
Perform the conversion
type Expression = Bound<Numeric, Self>
type Expression = Bound<Numeric, Self>
The expression being returned
Perform the conversion
Deserialize this value from the given Serde deserializer. Read more
Performs the /=
operation. Read more
Performs the /=
operation. Read more
Performs the /=
operation. Read more
Performs the /=
operation. Read more
Converts an i32
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an i64
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an i128
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an u32
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an u64
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an u128
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts a f32
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts a f64
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an isize
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an i8
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an i16
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts a usize
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
Converts an u8
to return an optional value of this type. If the
value cannot be represented by this type, then None
is returned. Read more
impl<__ST, __DB> FromSqlRow<__ST, __DB> for Decimal where
__DB: Backend,
Self: FromSql<__ST, __DB>,
impl<__ST, __DB> FromSqlRow<__ST, __DB> for Decimal where
__DB: Backend,
Self: FromSql<__ST, __DB>,
See the trait documentation.
The number of fields that this type will consume. Must be equal to
the number of times you would call row.take()
in build_from_row
Read more
The estimated exponential function, ex. Stops calculating when it is within
tolerance of roughly 0.0000002
. Read more
The estimated exponential function, ex. Stops calculating when it is within
tolerance of roughly 0.0000002
. Returns None
on overflow. Read more
The estimated exponential function, ex using the tolerance
provided as a hint
as to when to stop calculating. A larger tolerance will cause the number to stop calculating
sooner at the potential cost of a slightly less accurate result. Read more
The estimated exponential function, ex using the tolerance
provided as a hint
as to when to stop calculating. A larger tolerance will cause the number to stop calculating
sooner at the potential cost of a slightly less accurate result.
Returns None
on overflow. Read more
Raise self to the given integer exponent xy returning None
on overflow.
Raise self to the given unsigned integer exponent xy returning None
on overflow.
Raise self to the given floating point exponent xy returning None
on overflow.
Raise self to the given Decimal exponent: xy. If exp
is not whole then the approximation
ey*ln(x) is used. Read more
Raise self to the given Decimal exponent xy returning None
on overflow.
If exp
is not whole then the approximation ey*ln(x) is used. Read more
The square root of a Decimal. Uses a standard Babylonian method.
Calculates the natural logarithm for a Decimal calculated using Taylor’s series.
Calculates the checked natural logarithm for a Decimal calculated using Taylor’s series.
Returns None
for negative numbers or zero. Read more
Calculates the checked base 10 logarithm of a specified Decimal number.
Returns None
for negative numbers or zero. Read more
The Probability density function for a Normal distribution returning None
on overflow.
Performs the *=
operation. Read more
Performs the *=
operation. Read more
Performs the *=
operation. Read more
Performs the *=
operation. Read more
type FromStrRadixErr = Error
Convert from a string and radix (typically 2..=36
). Read more
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
Performs the %=
operation. Read more
Performs the %=
operation. Read more
Performs the %=
operation. Read more
Performs the %=
operation. Read more
Returns true if the number is positive and false if the number is zero or negative.
Returns true if the number is negative and false if the number is zero or positive.
Performs the -=
operation. Read more
Performs the -=
operation. Read more
Performs the -=
operation. Read more
Performs the -=
operation. Read more
Converts the value of self
to an i64
. If the value cannot be
represented by an i64
, then None
is returned. Read more
Converts the value of self
to an i128
. If the value cannot be
represented by an i128
(i64
under the default implementation), then
None
is returned. Read more
Converts the value of self
to a u64
. If the value cannot be
represented by a u64
, then None
is returned. Read more
Converts the value of self
to a u128
. If the value cannot be
represented by a u128
(u64
under the default implementation), then
None
is returned. Read more
Converts the value of self
to an f64
. Overflows may map to positive
or negative inifinity, otherwise None
is returned if the value cannot
be represented by an f64
. Read more
Converts the value of self
to an isize
. If the value cannot be
represented by an isize
, then None
is returned. Read more
Converts the value of self
to an i8
. If the value cannot be
represented by an i8
, then None
is returned. Read more
Converts the value of self
to an i16
. If the value cannot be
represented by an i16
, then None
is returned. Read more
Converts the value of self
to an i32
. If the value cannot be
represented by an i32
, then None
is returned. Read more
Converts the value of self
to a usize
. If the value cannot be
represented by a usize
, then None
is returned. Read more
Converts the value of self
to a u8
. If the value cannot be
represented by a u8
, then None
is returned. Read more
Converts the value of self
to a u16
. If the value cannot be
represented by a u16
, then None
is returned. Read more
Converts the value of self
to a u32
. If the value cannot be
represented by a u32
, then None
is returned. Read more
Auto Trait Implementations
impl RefUnwindSafe for Decimal
impl UnwindSafe for Decimal
Blanket Implementations
Mutably borrows from an owned value. Read more
Returns a reference to self
as a ToSql
trait object.
Convert self
to an expression for Diesel’s query builder. Read more
fn as_sql<'a, T>(&'a self) -> <&'a Self as AsExpression<T>>::Expression where
&'a Self: AsExpression<T>,
fn as_sql<'a, T>(&'a self) -> <&'a Self as AsExpression<T>>::Expression where
&'a Self: AsExpression<T>,
Convert &self
to an expression for Diesel’s query builder. Read more
type Output = T
type Output = T
Should always be Self