public void CalculateTest2()
{
var functions = new FunctionCollection();
var func = new UserFunction("f", new IExpression[] { new Number(1) }, 1);
Assert.AreEqual(Math.Log(1), func.Calculate(functions));
}
public void CalculateTest1()
{
var functions = new FunctionCollection();
functions.Add(new UserFunction("f", new IExpression[] { new Variable("x") }, 1), new Ln(new Variable("x")));
var func = new UserFunction("f", new IExpression[] { new Number(1) }, 1);
Assert.AreEqual(Math.Log(1), func.Calculate(functions));
}
public void ExecuteTest2()
{
var functions = new FunctionCollection();
var func = new UserFunction("f", new IExpression[] { new Number(1) }, 1);
Assert.Throws<KeyNotFoundException>(() => func.Execute(functions));
}
public void CalculateTest3()
{
var uf1 = new UserFunction("func", new[] { new Variable("x") }, 1);
var func = new DelegateExpression(p => (double)p.Parameters["x"] == 10 ? 0 : 1);
var funcs = new FunctionCollection();
funcs.Add(uf1, func);
var uf2 = new UserFunction("func", new[] { new Number(12) }, 1);
var result = uf2.Calculate(new ExpressionParameters(funcs));
Assert.AreEqual(1.0, result);
}
public void UndefFuncTest()
{
var key1 = new UserFunction("f", 0);
var key2 = new UserFunction("f", 1);
var functions = new FunctionCollection { { key1, new Number(1) }, { key2, new Number(2) } };
var undef = new Undefine(key1);
undef.Calculate(functions);
Assert.IsFalse(functions.ContainsKey(key1));
Assert.IsTrue(functions.ContainsKey(key2));
}
public void DefineFuncWithParamsTest()
{
var uf = new UserFunction("s", 1);
var func = new Sin(new Variable("x"));
var exp = new Define(uf, func);
var parameters = new ExpressionParameters();
var result = exp.Execute(parameters);
Assert.Equal(func, parameters.Functions[uf]);
Assert.Equal("The expression 'sin(x)' was assigned to the function 's(x1)'.", result);
}
public void DefineFuncTest()
{
var uf = new UserFunction("s", new IExpression[0], 0);
var func = new Sin(new Number(1));
var exp = new Define(uf, func);
var parameters = new ExpressionParameters();
var result = exp.Execute(parameters);
Assert.Equal(func, parameters.Functions[uf]);
Assert.Equal("The expression 'sin(1)' was assigned to the function 's()'.", result);
}
public void ExecuteRecursiveTest()
{
var expParams = new ExpressionParameters();
var exp = new If(new Equal(new Variable("x"), new Number(0)),
new Number(1),
new Mul(new Variable("x"), new UserFunction("f", new[] { new Sub(new Variable("x"), new Number(1)) }, 1)));
expParams.Functions.Add(new UserFunction("f", new[] { new Variable("x") }, 1), exp);
var func = new UserFunction("f", new[] { new Number(4) }, 1);
Assert.Equal(24.0, func.Execute(expParams));
}
public void UndefFuncWithParamsTest()
{
var key1 = new UserFunction("f", new IExpression[0], 0);
var key2 = new UserFunction("f", 1);
var functions = new FunctionCollection { { key1, new Number(1) }, { key2, new Number(2) } };
var undef = new Undefine(key2);
var result = undef.Execute(functions);
Assert.True(functions.ContainsKey(key1));
Assert.False(functions.ContainsKey(key2));
Assert.Equal("The 'f(x1)' function is removed.", result);
}
public FunctionViewModel(UserFunction function, IExpression value)
{
this.function = function;
this.value = value;
}
public void UserFunc()
{
var exp = new UserFunction("f", new IExpression[] { new Mul(new Number(2), new Number(2)) }, 1);
var expected = new UserFunction("f", new IExpression[] { new Number(4) }, 1);
SimpleTest(exp, expected);
}
public void UserFunctionDerivTest()
{
var parameters = new FunctionCollection();
var uf = new UserFunction("f", new IExpression[] { new Variable("x") }, 1);
parameters.Add(uf, new Sin(new Variable("x")));
var diff = Differentiate(uf, "x", parameters);
Assert.Equal("cos(x) * 1", diff.ToString());
}
public void UserFunctionDerivNullTest()
{
var uf = new UserFunction("f", new IExpression[] { new Variable("x") }, 1);
Assert.Throws<ArgumentNullException>(() => Differentiate(uf, "x", null));
}
/// <summary>
/// Differentiates the user function.
/// </summary>
/// <param name="expression">The expression.</param>
/// <param name="variable">The variable.</param>
/// <param name="parameters">The parameters.</param>
/// <returns>Returns the derivative.</returns>
protected virtual IExpression UserFunction(UserFunction expression, Variable variable, ExpressionParameters parameters)
{
var func = parameters.Functions[expression];
return _Differentiate(func, variable, parameters);
}