Equation

A Rust library for mathematical expression evaluation and simplification.

TODO

• Rewrite pest parsing as PrattParser;
• Modulo % & exponent ** support;
• Unary minus operator support;
• Support fractions as f32 f64;
• Support basic triggernomic ratio functions sine, cosine & tangent as sin, cos & tan;
• Support functions with additional arguments, atan2(y, x);
• Support evaluate steps parameter to break evaluation steps into a Vec<&str>;
• Support simplification & evaluation of algebraic expressions;
• Support for vectors and basic vector arithmetic & operations;

Getting started

Add the following lines to your Cargo.toml dependencies:

[dependencies]
equation = "1.0.0"

Examples

Evaluate basic arithmetic equations and return a f64.

use equation::evaluate;

fn main() {
    let result = evaluate("(1 + 2) * (1 + 2)"); // Returns Ok(9.0)
    match result {
        Ok(val) => println!("{}", val),
        Err(e) => println!("Error: {:?}", e),
    }
}

Support

Basic arithematic

evaluate("(1 + 2) * 1 + 2"); // Returns Ok(5.0)
evaluate("4 * 3");           // Returns Ok(12.0)
evaluate("8 / 2");           // Returns Ok(4.0)
evaluate("16 - 4");          // Returns Ok(12.0)

Negative calculations

Unary operator. Returns the negation of its operand.

evaluate("-4 * 3"); // Returns Ok(-12.0)
evaluate("-8 / 2"); // Returns Ok(-4.0)
evaluate("-(4 + 4)"); // Returns Ok(-8.0)

Exponentation

Calculates the base to the exponent power, base ^ exponent.

evaluate("2 ^ 8");   // Returns Ok(256.0)
evaluate("2 exp 9"); // Returns Ok(512.0)

Modulus

Returns the integer remainder of dividing the two operands.

evaluate("10 % 2");   // Returns Ok(0.0)
evaluate("10 % 4");   // Returns Ok(2.0)
evaluate("10 mod 3"); // Returns Ok(1.0)

Triggernomic functions

License

Licensed under MIT license (LICENSE-MIT | https://opensource.org/licenses/MIT) or under the Apache 2.0 (LICENSE-APACHE | https://opensource.org/license/apache-2-0/).