2 stable releases
1.0.1 | Jun 23, 2024 |
---|---|
1.0.0 | Jun 22, 2024 |
#2512 in Command line utilities
25KB
598 lines
sci-calc
An easy to use, fully functional scientific calculator library with command line interface.
$ sci-calc
2 + 2
= 4
a = ans * pi
= 12.566370614359172
cos(a)
= 1
exit
$
Features
- Variable assignment and recall
- Comprehensive built-in functions and constants
- Command line interface with line-editing and history recall
- Elegant, verbose error handling
Library
Add this crate to your project using cargo:
cargo add sci-calc
Below is a quick program implementing the sci-calc
crate, see the full documentation for details.
use std::io::stdin;
use sci_calc::{calculate, context::Context};
fn main() {
let mut ctx = Context::new();
loop {
let mut input = String::new();
std::io::stdin().read_line(&mut input).unwrap();
match calculate(input.as_str(), &mut ctx) {
Ok(result) => println!(" = {result}"),
Err(e) => println!("{e}"),
}
}
}
Command Line Interface
To compile from source:
cargo build --release --bin sci-calc
This will compile the binary to target/release/sci-calc
. Run the binary with an equation as an argument to evaluate that expression as a one-off, or run it with no arguments to use the calculator as a REPL. Use ctrl-C or the exit keyword to exit the program.
$ sci-calc 5 + 5
= 10
$ sci-calc
5 + 5
= 10
ans * 2
= 20
exit
$
Content
Basic Arithmetic
5 + 5 * 2^3
= 45
1.23e5 * 4.56e-6
= 0.56088
20!
= 2432902008176640000
Implemented operators in reverse order of precedence:
- Additive:
+
,-
- Multiplicative:
*
,/
,%
(modulus),//
(floored divide) - Exponentiation:
^
- Factorial:
!
Variable recall
a = 1 + 1
= 2
b = 2 * 2
= 4
a + b
= 6
ans + 4
= 10
Builtins
Vars:
e
= 2.718281828459045
2 * pi
= 6.283185307179586
ans / 2
= 3.141592653589793
Functions:
sqrt(2)
= 1.4142135623730951
ln(e)
= 1
2 * asin(1)
= 3.141592653589793
stddev(1, 2, 3)
= 0.816496580927726
All implemented functions:
- Square root
sqrt(x)
and n-rootroot(x, root)
- Factorial
fac(x)
, same as!
operator - Mean
mean(x, y, ...)
and standard deviationstddev(x, y, ...)
- Trig functions:
sin(x)
,cos(x)
, andtan(x)
- Inverse variants:
asin(x)
, ... - Hyperbolic variants:
sinh(x)
, ... - Inverse hyperbolic variants:
asinh(x)
, ...
- Inverse variants:
- Mininum
min(x, y)
and maximummax(x, y)
- Natural log
ln(x)
, log base-10log10(x)
, and log base-nlog(x, base)
- Absolute value
abs()
, roundround()
, floorfloor()
, and ceilingceil()
Errors
Parsing error examples
5 +
Parser error: Unexpected EOI
5 + + 5
Parser error: Unexpected token
| 5 + + 5
| └── here
5@ + 5
Parser error: Invalid token
| 5@ + 5
| └── here
Variable error examples
ans * 2
Calculation error: Cannot use 'ans' without a previous evaluated equation
pi = 3
Assignment error: Can't assign value to constant 'pi'
a + 5
Undefined identifier: Unknown variable 'a'
Dependencies
~6–15MB
~179K SLoC