/* @brief Loads numbers from input, accumulates their sum, sum of their squares and their count; calculated standard deviation and prints it
*/
private static int Main(string[] args)
{
MathComponents math = new MathComponents();
bool conversionSuccessful;
string input;
decimal square = 0;
decimal linearAccumulator = 0;
decimal quadraticAccumulator = 0;
int count = 0;
while (!string.IsNullOrEmpty(input = Console.ReadLine()))
{
conversionSuccessful = Decimal.TryParse(input, out decimal currentNumber);
if (!conversionSuccessful)
{
Console.WriteLine("Conversion error");
return(-1);
}
count++;
linearAccumulator = CheckNull(math.Add(linearAccumulator, currentNumber));
square = CheckNull(math.Exponentiate(currentNumber, 2));
quadraticAccumulator = CheckNull(math.Add(quadraticAccumulator, square));
}
if (count < 2)
{
Console.WriteLine("Minimum of 2 numbers required");
return(-1);
}
decimal average = CheckNull(math.Divide(1, count));
average = CheckNull(math.Multiply(average, linearAccumulator));
decimal deviationLeft = CheckNull(math.Subtract(count, 1));
deviationLeft = CheckNull(math.Divide(1, deviationLeft));
decimal deviationRight = CheckNull(math.Exponentiate(average, 2));
deviationRight = CheckNull(math.Multiply(count, deviationRight));
deviationRight = CheckNull(math.Subtract(quadraticAccumulator, deviationRight));
decimal deviation = CheckNull(math.Multiply(deviationLeft, deviationRight));
deviation = CheckNull(math.Root(2, deviation));
/* DEBUG INFO
* Console.WriteLine("N: " + count);
* Console.WriteLine("sum x: " + linearAccumulator);
* Console.WriteLine("sum x^2: " + quadraticAccumulator);
* Console.WriteLine("average x: " + average);
* // END INFO */
Console.WriteLine(deviation);
//Console.ReadLine();
return(0);
}
public void TestDivision()
{
//rules: cannnot divide by 0
MathComponents NewMath = new MathComponents();
// tests to check division functionality
decimal?result = NewMath.Divide(1, 1);
Assert.AreEqual(1, result);
result = NewMath.Divide(10, 5);
Assert.AreEqual(2, result);
result = NewMath.Divide(10, -2.5m);
Assert.AreEqual(-4, result);
result = NewMath.Divide(-18, -2);
Assert.AreEqual(9, result);
result = NewMath.Divide(0, 452871);
Assert.AreEqual(0, result);
result = NewMath.Divide(11656.5834m, 0.2541m);
Assert.AreEqual(45874, result);
result = NewMath.Divide(20.00m, 5.00m);
Assert.AreEqual(4, result);
result = NewMath.Divide(-2060309849.5m, -4517);
Assert.AreEqual(456123.5m, result);
result = NewMath.Divide(-6.25m, -0.05m);
Assert.AreEqual(125, result);
result = NewMath.Divide(0.008m, 0.008m);
Assert.AreEqual(1, result);
//test division by 0
result = NewMath.Divide(7744654.1254m, 0);
Assert.AreEqual(null, result);
result = NewMath.Divide(-451255.126359m, 0);
Assert.AreEqual(null, result);
result = NewMath.Divide(0, 0);
Assert.AreEqual(null, result);
// test length of returning value (max 9 significant digits)
result = NewMath.Divide(555555.55m, 5.222222m);
Assert.AreEqual(RoundOff(106382.9821865098m), result);
result = NewMath.Divide(3216546, 123.456m);
Assert.AreEqual(RoundOff(26054.1893468118195m), result);
// test error handling
result = NewMath.Divide(999999999, 0.5m);
Assert.AreEqual(null, result);
result = NewMath.Divide(898989898, 0.005m);
Assert.AreEqual(null, result);
}