Trait std::fmt::UpperExp
[−]
[src]
pub trait UpperExp { fn fmt(&self, &mut Formatter) -> Result<(), Error>; }
Format trait for the E
character.
The UpperExp
trait should format its output in scientific notation with an upper-case E
.
For more information on formatters, see the module-level documentation.
Examples
Basic usage with f32
:
let x = 42.0; // 42.0 is '4.2E1' in scientific notation assert_eq!(format!("{:E}", x), "4.2E1");
Implementing UpperExp
on a type:
use std::fmt; struct Length(i32); impl fmt::UpperExp for Length { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { let val = self.0; write!(f, "{}E1", val / 10) } } let l = Length(100); println!("l in scientific notation is: {:E}", l);