@Test
public void setSeveralExpressionsOk() throws Exception {
String expression = "-10 + myVar * (myVar + myVar2) / -myVar3";
ExpressionSolver target = new ExpressionSolver(expression);
target.setVariable("myVar", 1);
target.setVariable("myVar2", 2);
target.setVariable("myVar3", 3);
assertEquals(-11d, target.solve(), 0d);
expression = "myVar + myVar2";
target.setNewExpression(expression);
assertEquals(3d, target.solve(), 0d);
}
@Test
public void solveOk() throws Exception {
String expression = "1+ 2 + 3 * (5 - 4 / (1 + 1 * 3) )";
ExpressionSolver target = new ExpressionSolver(expression);
double actual = target.solve();
double expected = 15;
assertEquals(expected, actual, 0d);
}
@Test
public void setVariableOk() throws Exception {
String expression = "myVar";
ExpressionSolver target = new ExpressionSolver(expression);
String name = "myVar";
double value = 1.0;
target.setVariable(name, value);
assertEquals(1d, target.solve(), 0d);
}
@Test
public void functionInFunction() throws Exception {
String expression = "1 + myFunc(myFunc((x + 9*0)))";
ExpressionSolver target = new ExpressionSolver(expression);
target.setVariable("x", 2);
target.addFunction("myFunc", Arrays.asList("x"), "x*x");
double actual = target.solve();
double expected = 17;
assertEquals(expected, actual, 0d);
}
@Test
public void addFunction() throws Exception {
String expression = "myFunc(1, 2, 3)";
ExpressionSolver target = new ExpressionSolver(expression);
String name = "myFunc";
List<String> variables = Arrays.asList("x", "y", "z");
String functionExpression = "1 + x + y + z";
target.addFunction(name, variables, functionExpression);
assertEquals(7d, target.solve(), 0d);
}
@Test
public void functionInConstructor() throws Exception {
Function f =
new Function("myFunc", 1) {
@Override
public double apply(double... operands) {
return operands[0];
}
};
String expression = "1 + myFunc(1)";
ExpressionSolver target = new ExpressionSolver(expression, Arrays.asList(f));
double actual = target.solve();
double expected = 2;
assertEquals(expected, actual, 0d);
}
@Test
public void functionAndVarInConstructor() throws Exception {
Function f =
new Function("myFunc", 1) {
@Override
public double apply(double... operands) {
return operands[0];
}
};
String expression = "1 + myFunc(myVar)";
Map<String, Double> vars = new HashMap<String, Double>();
vars.put("myVar", 1d);
ExpressionSolver target = new ExpressionSolver(expression, vars, Arrays.asList(f));
double actual = target.solve();
double expected = 2;
assertEquals(expected, actual, 0d);
}