public void ComputeNpvCommand_ShouldComputeMultipleNpv()
{
var multipleRateLevels = new List <double> {
0.12, 0.15
};
discountRateLimiter.GetRateLevels(Arg.Any <double>(), Arg.Any <double>(), Arg.Any <double>())
.Returns(multipleRateLevels);
var npvParameter = new NpvParameter {
InitialInvestment = -35000
};
var sut = new NpvCalculatorViewModel(discountRateLimiter)
{
NpvParameter = npvParameter,
};
sut.CashFlows.Clear();
sut.CashFlows.Add(new CashFlow {
Cash = 10000, Index = 1
});
sut.CashFlows.Add(new CashFlow {
Cash = 27000, Index = 2
});
sut.CashFlows.Add(new CashFlow {
Cash = 19000, Index = 3
});
sut.ComputeNpvCommand.Execute(null);
sut.NetPresentValues.Count.ShouldBe(2);
Math.Round(sut.NetPresentValues.First().Value, 2).ShouldBe(8976.63);
Math.Round(sut.NetPresentValues.Last().Value, 2).ShouldBe(6604.34);
}
public NpvCalculatorViewModel(IDiscountRateLimiter npvCalculator)
{
this.npvCalculator = npvCalculator;
ComputeNpvCommand = new DelegateCommand <object>(ComputeNpvExecute, ComputeNpvCanExecute);
SetCashFlowsCommand = new DelegateCommand <object>(SetCashFlowsExecute);
NpvParameter = new NpvParameter
{
InitialInvestment = -100000,
LowerBoundDiscountRate = 0.0365,
UpperBoundDiscountRate = 0.037,
DiscountRateIncrement = 0.0001,
ProjectLife = 3
};
CashFlows.AddRange(new[] {
new CashFlow {
Index = 0, Cash = 10000
},
new CashFlow {
Index = 1, Cash = 10000
},
new CashFlow {
Index = 2, Cash = 10000
}
});
}
public void ComputeNpvCommand_ShouldComputeNpv()
{
var oneRateLevelOnly = new List <double> {
0.12
};
discountRateLimiter.GetRateLevels(Arg.Any <double>(), Arg.Any <double>(), Arg.Any <double>())
.Returns(oneRateLevelOnly);
var npvParameter = new NpvParameter {
InitialInvestment = -35000
};
var sut = new NpvCalculatorViewModel(discountRateLimiter)
{
NpvParameter = npvParameter,
};
sut.CashFlows.Clear();
sut.CashFlows.Add(new CashFlow {
Cash = 10000, Index = 1
});
sut.CashFlows.Add(new CashFlow {
Cash = 27000, Index = 2
});
sut.CashFlows.Add(new CashFlow {
Cash = 19000, Index = 3
});
sut.ComputeNpvCommand.Execute(null);
sut.NetPresentValues.Count.ShouldBe(1);
Math.Round(sut.NetPresentValues.First().Value, 2).ShouldBe(8976.63);
//ref: https://www.investopedia.com/ask/answers/032615/what-formula-calculating-net-present-value-npv.asp
}
private bool ComputeNpvCanExecute(object param)
{
var canExecute = NpvParameter.IsValid() &&
CashFlows.Any();
return(canExecute);
}
