CalculatorModel(string expression)
{
this.expression = expression;
db = new DBContext();
operations = new Dictionary <string, Func <double, double, double> >
{
{ "+", (x, y) => x + y },
{ "-", (x, y) => x - y },
{ "*", (x, y) => x * y },
{ "/", (x, y) => x / y },
{ "mod", (x, y) => x % y },
{ "pow", (x, y) => Math.Pow(x, y) },
{ "sqrt", (x, y) => y != 0 ? Math.Pow(x, 1 / y): 1 / y }
};
db.AddExpression("127.0.0.1", expression);
}