/* @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);
}
/**
* @brief Tests to check root functionality
* @brief root only from positive numbers
* @brief testing if length is max 9 significant digits
*/
public void TestRoot()
{
// rules: root only from positive numbers
MathComponents NewMath = new MathComponents();
// tests to check root functionality
decimal?result = NewMath.Root(1, 1);
Assert.AreEqual(1, result);
result = NewMath.Root(2, 25);
Assert.AreEqual(5, result);
result = NewMath.Root(3.00m, 125.00m);
Assert.AreEqual(5, result);
result = NewMath.Root(0.25m, 30);
Assert.AreEqual(810000, result);
result = NewMath.Root(-4, 16);
Assert.AreEqual(0.5m, result);
result = NewMath.Root(-0.5m, 8);
Assert.AreEqual(0.015625m, result);
result = NewMath.Root(0.5m, 10);
Assert.AreEqual(100, result);
result = NewMath.Root(4, 22667121);
Assert.AreEqual(69, result);
result = NewMath.Root(0.5m, 12586);
Assert.AreEqual(158407396, result);
// test undefined values
result = NewMath.Root(0, 752041.44221m);
Assert.AreEqual(null, result);
result = NewMath.Root(4, -125);
Assert.AreEqual(null, result);
result = NewMath.Root(-3, -12.4m);
Assert.AreEqual(null, result);
result = NewMath.Root(2.4m, -23.25874m);
Assert.AreEqual(null, result);
// test length of returning value (max 9 significant digits)
result = NewMath.Root(2, 0.3m);
Assert.AreEqual(RoundOff(0.54772255m), result);
result = NewMath.Root(3, 5);
Assert.AreEqual(RoundOff(1.7099759466766m), result);
result = NewMath.Root(0.3m, 65);
Assert.AreEqual(RoundOff(1104191.8114525m), result);
// test error handling
result = NewMath.Root(0.5m, 50000);
Assert.AreEqual(null, result);
result = NewMath.Root(0.2m, 600);
Assert.AreEqual(null, result);
}