Open Source Libs 👉Expression 👉Go Exprtk

Go Mathematical Expression Toolkit

The Go Expression Toolkit (Go-ExprTk) is a wrapper library based on C++ Mathematical Expression Toolkit Library (ExprTk).

It is a simple to use, easy to integrate and extremely efficient run-time mathematical expression parser and evaluation engine.

Go-ExprTk supports numerous forms of functional, logical and vector processing semantics and is very easily extendible.

Installation

go get github.com/Pramod-Devireddy/go-exprtk

Examples

package main

import (
    "fmt"

    "github.com/Pramod-Devireddy/go-exprtk"
)

func main() {
    exprtkObj := exprtk.NewExprtk()
    defer exprtkObj.Delete()

    exprtkObj.SetExpression("(x + 2)*(y-2)")

    exprtkObj.AddDoubleVariable("x")
    exprtkObj.AddDoubleVariable("y")

    err := exprtkObj.CompileExpression()
    if err != nil {
        fmt.Println(err.Error())
        return
    }

    exprtkObj.SetDoubleVariableValue("x", 18)
    exprtkObj.SetDoubleVariableValue("y", 32)

    fmt.Println(exprtkObj.GetEvaluatedValue())
}

Check out more Examples

⚡ Features

The Go-ExprTk library has the following capabilities:

Mathematical operators (+, -, *, /, %, ^)
Functions (min, max, avg, sum, abs, ceil, floor, round, roundn, exp, log, log10, logn, pow, root, sqrt, clamp, inrange, swap)
Trigonometry (sin, cos, tan, acos, asin, atan, atan2, cosh, cot, csc, sec, sinh, tanh, d2r, r2d, d2g, g2d, hyp)
Equalities & Inequalities (=, ==, <>, !=, <, <=, >, >=)
Assignment (:=, +=, -=, *=, /=, %=)
Logical operators (and, nand, nor, not, or, xor, xnor, mand, mor)
Control structures (if-then-else, ternary conditional, switch case, return-statement)
Loop structures (while loop, for loop, repeat until loop, break, continue)
Optimization of expressions (constant folding, strength reduction, operator coupling, special functions and dead code elimination)
String operations (equalities, inequalities, logical operators, concatenation and sub-ranges)
Expression local variables, vectors and strings
User defined variables, vectors, strings, constants and function support
Multivariate function composition
Multiple sequence point and sub expression support
Numeric integration and differentiation
Vector Processing: BLAS-L1 (axpy, axpby, axpb), all/any-true/false, count, rotate-left/right, shift-left/right, sort, nth_element, iota, sum, kahan-sum, dot-product, copy

❤️ Credits

This module could not be possible without the ExprTk library by Arash Partow and the idea of creating the wrapper module by Narayana Rao G S

Published under MIT License

Go Exprtk