static void Main(string[] args)
{
ExpressionParser calculator = new ExpressionParser("sqrt(abs(x))");
for (double x = -10; x <= 10; x++)
{
calculator.SetValue("x", x);
Console.WriteLine(calculator.Evaluate());
}
TestParser("pi", null, Math.PI);
TestParser("1+2+3+4", null, 10);
TestParser("(1+2)*(3+4)", null, 21);
TestParser("4^-2", null, 1.0 / 16);
TestParser("4^(-2)", null, 1.0 / 16);
TestParser("4^-2*4", null, 0.25);
TestParser("sqrt(25 - abs(3 * (2 - 5)))", null, 4);
TestParser("sqrt(x)", new Dictionary <string, double>()
{
{ "x", 625 }
}, 25);
TestParser("sin(arcsin(x))", new Dictionary <string, double>()
{
{ "x", 0.4 }
}, 0.4);
TestParser("e^pi - exp(2*acos(0))", null, 0);
TestParser("lg(10000)", null, 4);
TestParser("cbrt(8)", null, 2);
TestParser("cbrt(-8)", null, -2);
TestParser("2^2^3", null, 256);
TestParser("(2^2)^3", null, 64);
TestParser("2^(2^3)", null, 256);
TestParser("-1^2", null, -1);
TestParser("(-1)^2", null, 1);
TestParser("2^-2^2", null, 1.0 / 16);
TestParser("2^(-2)^2", null, 16);
TestParser("(2^-2)^2", null, 1.0 / 16);
TestParser("2^-2^-2", null, Math.Pow(2, -0.25));
TestParser("max(6, 8)", null, 8);
TestParser("min(6, 8)", null, 6);
TestParser("log(2, 8)", null, 3);
TestParser("pow(2, 8)", null, 256);
TestParser("root(4, 256)", null, 4);
TestParser("root(8 / 4 + log(2, 4), 2 ^ 8)", null, 4);
TestParser("(x1 + x2) ^ 2", new Dictionary <string, double>()
{
{ "x1", 3 }, { "x2", 5 }
}, 64);
TestParser("(x123 + x26x) ^ 2", new Dictionary <string, double>()
{
{ "x123", 3 }, { "x26x", 5 }
}, 64);
Console.ReadKey();
}
static void TestParser(string expression, Dictionary <string, double> variables, double answer, double eps = 1e-10)
{
ExpressionParser parser = new ExpressionParser(expression);
if (variables != null)
{
foreach (string name in variables.Keys)
{
parser.SetValue(name, variables[name]);
}
}
double result = parser.Evaluate();
if (Math.Abs(result - answer) > eps)
{
Console.WriteLine("FAILED: {0}: {1} != {2}", expression, result, answer);
}
}