flutter_exprtk 0.0.1

exptrk math expression library for flutter.

example/lib/main.dart

import 'dart:async';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter_exprtk/expression.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {

  static Future<List<double>> computeExpression (dynamic param) async {
    final exp2 = Expression(
      expression: "clamp(-1.0,sin(2 * pi * x) + cos(x / 2 * pi),+1.0)",
      variables: { "x": 0 }
    );
    final List<double> results = [];

    for (double x = -5; x <= 5; x += 0.001)
    {
      exp2["x"] = x;
      results.add(exp2.value);
    }
    exp2.clear();

    return results;
  }

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Expression plugin example'),
        ),
        body: Center(
          child: OutlinedButton(
            onPressed: () async {
              final results = await compute(computeExpression, null);
              print("Results $results");
            },
            child: Text("Run"),
          )
        ),
      ),
    );
  }
}