Crate xxcalc [−] [src]
xxcalc
is a crate which provides an embeddable floating-point
polynomial calculator and linear solver.
You can use xxcalc
to embed mathematical expression evaluator
in your own programs. By default the calculator provides addition +
,
subtraction -
, multiplication *
, division /
and exponentation ^
operators. Some functions such as log
and log10
are implemented,
as well as pi
and e
constants. This is a polynomial calculator, so
you can perform arithmetic operations on polynomials (using x
symbol
by default) - a simple floating-point number is just a special case of
a polynomial (the constant polynomial, polynomial of degree zero).
Furthermore the crate is well structurized and documented - you can use pieces it provides to create your own custom solutions (you can use or change a tokenizer, parser and evaluator however you want). Look at implementations of PolynomialParser, LinearSolverParser, PolynomialEvaluator or LinearSolverEvaluator to see how to extend default implementations.
With the crate a xxcalc
binary is provided which can be used as a
standalone CLI calculator (which can be replacement for bc
command).
If the crate is installed with a feature "interactive" enabled, a history
of commands is enabled.
Whole library is meticulously tested, use cargo test
to run unit tests
(including doc examples), cargo bench
will run simple benchmarks, while
cargo bench -- --ignored
will run more computation-heavy benchmarks.
Examples
You can easily take a LinearSolver or PolynomialCalculator to embed mathematical engine inside your programs.
use xxcalc::linear_solver::LinearSolver; use xxcalc::calculator::Calculator; use xxcalc::polynomial::Polynomial; assert_eq!(LinearSolver.process("2x + 1 = 2(1-x)"), Ok(Polynomial::constant(0.25))); assert_eq!(LinearSolver.process("0.1*-2+4"), Ok(Polynomial::constant(3.8)));
Please see documentation for PolynomialCalculator for more examples.
Modules
calculator |
Calculator is an easy to use generic method of evaluating string expressions. |
evaluator |
Evaluator is a TokensReducer, it takes token in RPN form and evaluates its Polynomial value. |
linear_solver |
Defines a LinearSolver which extends a PolynomialCalculator with ability of solving single linear equation. |
parser |
Parser is a TokensProcessor, it takes Tokens in a classical infix form and transforms them into Reverse Polish Notation form for further evaluation. |
polynomial |
Defines Polynomial expression with basic operators on it. |
polynomial_calculator |
Defines a PolynomialCalculator with common arithmetic operations, functions and constants already defined. |
tokenizer |
Tokenizer is a StringProcessor, it takes string expression and converts it into Tokens for further processing. |
Structs
Tokens |
Tokens is a compound storage for list of tokens with their identifiers. |
Enums
EvaluationError |
An error that occurs during token reduction, usually by an evaluator. |
ParsingError |
An error that occurs during token processing, usually by a parser. |
Token |
Token is a basic unit returned after tokenization using a StringProcessor. |
Traits
StringProcessor |
Transforms text expression into list of tokens. |
TokensProcessor |
Transforms list of tokens into another list of tokens. |
TokensReducer |
Evaluates list of tokens into a single Polynomial value. |
Type Definitions
Identifiers |
Vector of unique identifiers. |
TokenList |
List of tokens with their position. |