Struct Context 

pub struct Context { /* private fields */ }

Context contains parameters, like rounding mode and precision, as well as constant values, and is used with expr! macro.

Implementations

impl Context

pub fn new( p: usize, rm: RoundingMode, cc: Consts, emin: i32, emax: i32, ) -> Context

Create a new context. The value of emin will be clamped to a range between EXPONENT_MIN and 0. The value of emax will be clamped to a range between 0 and EXPONENT_MAX.

pub fn to_raw_parts(self) -> (usize, RoundingMode, Consts, i32, i32)

Destructures the context and returns its parts: target precision, rounding mode, constant cache, minimum exponent, maximum exponent.

pub fn set_precision(&mut self, p: usize)

Sets the precision of the context.

pub fn set_rounding_mode(&mut self, rm: RoundingMode)

Sets the rounding mode of the context.

pub fn set_consts(&mut self, cc: Consts)

Sets the constant cache of the context.

pub fn set_emin(&mut self, emin: i32)

Sets the minimum exponent. The value of emin will be clamped to a range between EXPONENT_MIN and 0.

pub fn set_emax(&mut self, emax: i32)

Sets the maximum exponent. The value of emax will be clamped to a range between 0 and EXPONENT_MAX.

pub fn precision(&self) -> usize

Returns the precision of the context.

pub fn rounding_mode(&self) -> RoundingMode

Returns the rounding mode of the context.

pub fn consts(&mut self) -> &mut Consts

Returns a mutable reference to the constant cache of the context.

pub fn const_pi(&mut self) -> ExactNum

Returns the value of the pi number.

pub fn const_e(&mut self) -> ExactNum

Returns the value of the Euler number.

pub fn const_ln2(&mut self) -> ExactNum

Returns the value of the natural logarithm of 2.

pub fn const_ln10(&mut self) -> ExactNum

Returns the value of the natural logarithm of 10.

pub fn const_sqrt2(&mut self) -> ExactNum

Returns √2.

pub fn const_phi(&mut self) -> ExactNum

Returns the golden ratio φ.

pub fn const_euler_gamma(&mut self) -> ExactNum

Returns the Euler–Mascheroni constant γ.

pub fn emin(&self) -> i32

Returns the minimum exponent.

pub fn emax(&self) -> i32

Returns the maximum exponent.

pub fn with_rounding_mode<F, R>(&mut self, rm: RoundingMode, f: F) -> R

where F: FnOnce(&mut Context) -> R,

Runs f with rounding mode rm, then restores the previous mode. If f panics, the previous mode is not restored.

pub fn clone(&self) -> Result<Context, Error>

Clones self and returns the cloned context.

Errors

• MemoryAllocation: failed to allocate memory for the constants cache.

Trait Implementations

impl Contextable for Context

fn precision(&self) -> usize

Returns the precision of the context.

fn rounding_mode(&self) -> RoundingMode

Returns the rounding mode of the context.

fn consts(&mut self) -> &mut Consts

Returns a mutable reference to the constant cache of the context.

fn const_pi(&mut self) -> ExactNum

Returns the value of the pi number.

fn const_e(&mut self) -> ExactNum

Returns the value of the Euler number.

fn const_ln2(&mut self) -> ExactNum

Returns the value of the natural logarithm of 2.

fn const_ln10(&mut self) -> ExactNum

Returns the value of the natural logarithm of 10.

fn const_sqrt2(&mut self) -> ExactNum

√2 at the context precision.

fn const_phi(&mut self) -> ExactNum

Golden ratio φ at the context precision.

fn const_euler_gamma(&mut self) -> ExactNum

Euler–Mascheroni constant γ at the context precision.

fn emin(&self) -> i32

Returns the minimum exponent.

fn emax(&self) -> i32

Returns the maximum exponent.

impl Debug for Context

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.