Add floor and ceiling functions

src/Mathematics.NET/Core/IReal.cs

@@ -46,6 +46,16 @@ public interface IReal<T>
     /// <summary>The backing value of the type</summary>
     double Value { get; }
 
+    /// <summary>Compute the ceiling function of a value</summary>
+    /// <param name="x">A value</param>
+    /// <returns>The smallest integer greater than or equal to the value</returns>
+    static abstract T Ceiling(T x);
+
+    /// <summary>Compute the floor function of a value</summary>
+    /// <param name="x">A value</param>
+    /// <returns>The largest integer less than or equal to the value</returns>
+    static abstract T Floor(T x);
+
     /// <summary>Check if a value is negative infinity</summary>
     /// <param name="x">The value to check</param>
     /// <returns><c>true</c> if the value is negative infinity; otherwise, <c>false</c></returns>

src/Mathematics.NET/Core/Rational.cs

@@ -436,8 +436,16 @@ public static bool TryParse(ReadOnlySpan<char> s, NumberStyles style, IFormatPro
 
     public static Rational<T> Abs(Rational<T> x) => new(T.Abs(x._numerator), T.Abs(x._denominator));
 
+    public static Rational<T> Ceiling(Rational<T> x)
+    {
+        var (quotient, remainder) = T.DivRem(x._numerator, x._denominator);
+        return remainder == T.Zero ? quotient : quotient + T.One;
+    }
+
     public static Rational<T> Conjugate(Rational<T> x) => x;
 
+    public static Rational<T> Floor(Rational<T> x) => T.DivRem(x._numerator, x._denominator).Quotient;
+
     public static Rational<T> FromDouble(double x) => (Rational<T>)x;
 
     public static Rational<T> FromReal(Real x) => (Rational<T>)x;

src/Mathematics.NET/Core/Real.cs

@@ -260,8 +260,12 @@ public static bool TryParse(ReadOnlySpan<char> s, NumberStyles style, IFormatPro
 
     public static Real Abs(Real x) => Math.Abs(x._value);
 
+    public static Real Ceiling(Real x) => Math.Ceiling(x._value);
+
     public static Real Conjugate(Real x) => x;
 
+    public static Real Floor(Real x) => Math.Floor(x._value);
+
     public static Real FromDouble(double x) => new(x);
 
     public static Real FromReal(Real x) => x;