public void HasPatternTest()
{
int returnVal;
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 2, 6, 12, 20, 30, 42, 56, 72 }, out returnVal), true);
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 2, 6, 12, 20 }, out returnVal), true);
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 0, 1, 3, 7, 15, 31, 63, 127, 255, 511, 1023 }, out returnVal), false); // dangerous case that will not work because of 2^x
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 0, 2, 8, 26, 80, 242, 728, 2186, 6560 }, out returnVal), false);
}
public void HasPatternForceCheck()
{
int index;
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 1, 2, 3, 4, 5, 6 }, out index), true);
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 1, 2, 3, 4, 5, 7 }, out index, true), false);
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 0, 1, 4, 9, 16, 25 }, out index, true), true);
Assert.AreEqual(FiniteCalculus.HasPattern(new double[] { 0, 1, 4, 9, 16, 26 }, out index, true), false);
}
public void GetCoefficientsForNthTermTest()
{
int index;
double[] sequence = { 1, 2, 3, 4, 5 };
FiniteCalculus.HasPattern(sequence, out index);
var a = FiniteCalculus.GetCoefficientsForNthTerm(sequence, index);
Assert.AreEqual(a[0], 1.0);
Assert.AreEqual(a[1], 0.0);
}
public void GetExpressionForNthTermTest()
{
int index;
double[] sequence = { 1, 2, 3, 4, 5 };
FiniteCalculus.HasPattern(sequence, out index);
var expression = FiniteCalculus.GetExpressionForNthTerm(FiniteCalculus.GetCoefficientsForNthTerm(sequence, index));
Assert.AreEqual(expression, "1x");
double[] sequence2 = { 1, 4, 8, 13 };
FiniteCalculus.HasPattern(sequence2, out index);
var expression2 = FiniteCalculus.GetExpressionForNthTerm(FiniteCalculus.GetCoefficientsForNthTerm(sequence2, index));
Assert.AreEqual(expression2, "0.8888888889x^2+0.4444444444x+0.1111111111");
}
protected void Button1_Click(object sender, EventArgs e)
{
if (TextBox1.Text != "")
{
var tokens = TextBox1.Text.Split(',');
double[] seq;
try
{
seq = Array.ConvertAll(tokens, double.Parse);
}
catch
{
Label1.Text = "Could not convert the sequence into an array.";
return;
}
int degree;
if (FiniteCalculus.HasPattern(seq, out degree))
{
var coeff = FiniteCalculus.GetCoefficientsForNthSum(seq, degree);
var output = FiniteCalculus.GetExpressionForNthSum(coeff);
Label1.Text = output;
}
else
{
Label1.Text = "Not enough terms to spot a pattern or not a polynomial sequence.";
}
}
else
{
Label1.Text = "No sequence was entered.";
}
}