Polynomial long division: Difference between revisions
→{{header|Clojure}}
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Line 645:
delete [] r;
}</lang>
=={{header|C#|C sharp}}==
{{trans|Java}}
<lang csharp>using System;
namespace PolynomialLongDivision {
class Solution {
public Solution(double[] q, double[] r) {
Quotient = q;
Remainder = r;
}
public double[] Quotient { get; }
public double[] Remainder { get; }
}
class Program {
static int PolyDegree(double[] p) {
for (int i = p.Length - 1; i >= 0; --i) {
if (p[i] != 0.0) return i;
}
return int.MinValue;
}
static double[] PolyShiftRight(double[] p, int places) {
if (places <= 0) return p;
int pd = PolyDegree(p);
if (pd + places >= p.Length) {
throw new ArgumentOutOfRangeException("The number of places to be shifted is too large");
}
double[] d = new double[p.Length];
p.CopyTo(d, 0);
for (int i = pd; i >= 0; --i) {
d[i + places] = d[i];
d[i] = 0.0;
}
return d;
}
static void PolyMultiply(double[] p, double m) {
for (int i = 0; i < p.Length; ++i) {
p[i] *= m;
}
}
static void PolySubtract(double[] p, double[] s) {
for (int i = 0; i < p.Length; ++i) {
p[i] -= s[i];
}
}
static Solution PolyLongDiv(double[] n, double[] d) {
if (n.Length != d.Length) {
throw new ArgumentException("Numerator and denominator vectors must have the same size");
}
int nd = PolyDegree(n);
int dd = PolyDegree(d);
if (dd < 0) {
throw new ArgumentException("Divisor must have at least one one-zero coefficient");
}
if (nd < dd) {
throw new ArgumentException("The degree of the divisor cannot exceed that of the numerator");
}
double[] n2 = new double[n.Length];
n.CopyTo(n2, 0);
double[] q = new double[n.Length];
while (nd >= dd) {
double[] d2 = PolyShiftRight(d, nd - dd);
q[nd - dd] = n2[nd] / d2[nd];
PolyMultiply(d2, q[nd - dd]);
PolySubtract(n2, d2);
nd = PolyDegree(n2);
}
return new Solution(q, n2);
}
static void PolyShow(double[] p) {
int pd = PolyDegree(p);
for (int i = pd; i >= 0; --i) {
double coeff = p[i];
if (coeff == 0.0) continue;
if (coeff == 1.0) {
if (i < pd) {
Console.Write(" + ");
}
} else if (coeff == -1.0) {
if (i < pd) {
Console.Write(" - ");
} else {
Console.Write("-");
}
} else if (coeff < 0.0) {
if (i < pd) {
Console.Write(" - {0:F1}", -coeff);
} else {
Console.Write("{0:F1}", coeff);
}
} else {
if (i < pd) {
Console.Write(" + {0:F1}", coeff);
} else {
Console.Write("{0:F1}", coeff);
}
}
if (i > 1) Console.Write("x^{0}", i);
else if (i == 1) Console.Write("x");
}
Console.WriteLine();
}
static void Main(string[] args) {
double[] n = { -42.0, 0.0, -12.0, 1.0 };
double[] d = { -3.0, 1.0, 0.0, 0.0 };
Console.Write("Numerator : ");
PolyShow(n);
Console.Write("Denominator : ");
PolyShow(d);
Console.WriteLine("-------------------------------------");
Solution sol = PolyLongDiv(n, d);
Console.Write("Quotient : ");
PolyShow(sol.Quotient);
Console.Write("Remainder : ");
PolyShow(sol.Remainder);
}
}
}</lang>
{{out}}
<pre>Numerator : x^3 - 12.0x^2 - 42.0
Denominator : x - 3.0
-------------------------------------
Quotient : x^2 - 9.0x - 27.0
Remainder : -123.0</pre>
=={{header|Clojure}}==
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