Distributions: bring back public static IsValidParameterSet functions

src/Numerics/Distributions/Bernoulli.cs

@@ -79,6 +79,15 @@ namespace MathNet.Numerics.Distributions
             return "Bernoulli(p = " + _p + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="p">The probability (p) of generating one. Range: 0 ≤ p ≤ 1.</param>
+        public static bool IsValidParameterSet(double p)
+        {
+            return p >= 0.0 && p <= 1.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Beta.cs

@@ -88,6 +88,16 @@ namespace MathNet.Numerics.Distributions
             return "Beta(α = " + _shapeA + ", β = " + _shapeB + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="a">The α shape parameter of the Beta distribution. Range: α ≥ 0.</param>
+        /// <param name="b">The β shape parameter of the Beta distribution. Range: β ≥ 0.</param>
+        public static bool IsValidParameterSet(double a, double b)
+        {
+            return a >= 0.0 && b >= 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Binomial.cs

@@ -86,6 +86,16 @@ namespace MathNet.Numerics.Distributions
             return "Binomial(p = " + _p + ", n = " + _trials + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="p">The success probability (p) in each trial. Range: 0 ≤ p ≤ 1.</param>
+        /// <param name="n">The number of trials (n). Range: n ≥ 0.</param>
+        public static bool IsValidParameterSet(double p, int n)
+        {
+            return p >= 0.0 && p <= 1.0 && n >= 0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Categorical.cs

@@ -123,7 +123,7 @@ namespace MathNet.Numerics.Distributions
         /// </summary>
         /// <param name="p">An array of nonnegative ratios: this array does not need to be normalized as this is often impossible using floating point arithmetic.</param>
         /// <returns>If any of the probabilities are negative returns <c>false</c>, or if the sum of parameters is 0.0; otherwise <c>true</c></returns>
-        static bool IsValidProbabilityMass(double[] p)
+        public static bool IsValidProbabilityMass(double[] p)
         {
             var sum = 0.0;
             for (int i = 0; i < p.Length; i++)
@@ -145,7 +145,7 @@ namespace MathNet.Numerics.Distributions
         /// </summary>
         /// <param name="cdf">An array of nonnegative ratios: this array does not need to be normalized as this is often impossible using floating point arithmetic.</param>
         /// <returns>If any of the probabilities are negative returns <c>false</c>, or if the sum of parameters is 0.0; otherwise <c>true</c></returns>
-        static bool IsValidCumulativeDistribution(double[] cdf)
+        public static bool IsValidCumulativeDistribution(double[] cdf)
         {
             var last = 0.0;
             for (int i = 0; i < cdf.Length; i++)

src/Numerics/Distributions/Cauchy.cs

@@ -87,6 +87,16 @@ namespace MathNet.Numerics.Distributions
             return "Cauchy(x0 = " + _location + ", γ = " + _scale + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="location">The location (x0) of the distribution.</param>
+        /// <param name="scale">The scale (γ) of the distribution. Range: γ > 0.</param>
+        public static bool IsValidParameterSet(double location, double scale)
+        {
+            return scale > 0.0 && !Double.IsNaN(location);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Chi.cs

@@ -78,6 +78,15 @@ namespace MathNet.Numerics.Distributions
             return "Chi(k = " + _freedom + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="freedom">The degrees of freedom (k) of the distribution. Range: k > 0.</param>
+        public static bool IsValidParameterSet(double freedom)
+        {
+            return freedom > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/ChiSquared.cs

@@ -76,6 +76,15 @@ namespace MathNet.Numerics.Distributions
             return "ChiSquared(k = " + _freedom + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="freedom">The degrees of freedom (k) of the distribution. Range: k > 0.</param>
+        public static bool IsValidParameterSet(double freedom)
+        {
+            return freedom > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/ContinuousUniform.cs

@@ -89,6 +89,16 @@ namespace MathNet.Numerics.Distributions
             return "ContinuousUniform(Lower = " + _lower + ", Upper = " + _upper + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="lower">Lower bound. Range: lower ≤ upper.</param>
+        /// <param name="upper">Upper bound. Range: lower ≤ upper.</param>
+        public static bool IsValidParameterSet(double lower, double upper)
+        {
+            return lower <= upper && !Double.IsInfinity(lower) && !Double.IsInfinity(upper);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/ConwayMaxwellPoisson.cs

@@ -107,6 +107,16 @@ namespace MathNet.Numerics.Distributions
             return "ConwayMaxwellPoisson(λ = " + _lambda + ", ν = " + _nu + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="lambda">The lambda (λ) parameter. Range: λ > 0.</param>
+        /// <param name="nu">The rate of decay (ν) parameter. Range: ν ≥ 0.</param>
+        public static bool IsValidParameterSet(double lambda, double nu)
+        {
+            return lambda > 0.0 && nu >= 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Dirichlet.cs

@@ -117,15 +117,11 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Checks whether the parameters of the distribution are valid: no
-        /// parameter can be less than zero and at least one parameter should be
-        /// larger than zero.
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// No parameter can be less than zero and at least one parameter should be larger than zero.
         /// </summary>
-        /// <param name="alpha">The parameters of the Dirichlet distribution.
-        /// </param>
-        /// <returns><c>true</c> when the parameters are valid, <c>false</c>
-        /// otherwise.</returns>
-        static bool IsValidParameterSet(double[] alpha)
+        /// <param name="alpha">The parameters of the Dirichlet distribution.</param>
+        public static bool IsValidParameterSet(double[] alpha)
         {
             var allzero = true;
 

src/Numerics/Distributions/DiscreteUniform.cs

@@ -82,6 +82,16 @@ namespace MathNet.Numerics.Distributions
             return "DiscreteUniform(Lower = " + _lower + ", Upper = " + _upper + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="lower">Lower bound. Range: lower ≤ upper.</param>
+        /// <param name="upper">Upper bound. Range: lower ≤ upper.</param>
+        public static bool IsValidParameterSet(int lower, int upper)
+        {
+            return lower <= upper;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Erlang.cs

@@ -104,6 +104,16 @@ namespace MathNet.Numerics.Distributions
             return "Erlang(k = " + _shape + ", λ = " + _rate + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="shape">The shape (k) of the Erlang distribution. Range: k ≥ 0.</param>
+        /// <param name="rate">The rate or inverse scale (λ) of the Erlang distribution. Range: λ ≥ 0.</param>
+        public static bool IsValidParameterSet(double shape, double rate)
+        {
+            return shape >= 0.0 && rate >= 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Exponential.cs

@@ -78,6 +78,15 @@ namespace MathNet.Numerics.Distributions
             return "Exponential(λ = " + _rate + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="rate">The rate (λ) parameter of the distribution. Range: λ ≥ 0.</param>
+        public static bool IsValidParameterSet(double rate)
+        {
+            return rate >= 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/FisherSnedecor.cs

@@ -80,6 +80,16 @@ namespace MathNet.Numerics.Distributions
             return "FisherSnedecor(d1 = " + _freedom1 + ", d2 = " + _freedom2 + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="d1">The first degree of freedom (d1) of the distribution. Range: d1 > 0.</param>
+        /// <param name="d2">The second degree of freedom (d2) of the distribution. Range: d2 > 0.</param>
+        public static bool IsValidParameterSet(double d1, double d2)
+        {
+            return d1 > 0.0 && d2 > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Gamma.cs

@@ -113,6 +113,16 @@ namespace MathNet.Numerics.Distributions
             return "Gamma(α = " + _shape + ", β = " + _rate + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="shape">The shape (k, α) of the Gamma distribution. Range: α ≥ 0.</param>
+        /// <param name="rate">The rate or inverse scale (β) of the Gamma distribution. Range: β ≥ 0.</param>
+        public static bool IsValidParameterSet(double shape, double rate)
+        {
+            return shape >= 0.0 && rate >= 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Geometric.cs

@@ -77,6 +77,15 @@ namespace MathNet.Numerics.Distributions
             return "Geometric(p = " + _p + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="p">The probability (p) of generating one. Range: 0 ≤ p ≤ 1.</param>
+        public static bool IsValidParameterSet(double p)
+        {
+            return p >= 0.0 && p <= 1.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Hypergeometric.cs

@@ -86,6 +86,17 @@ namespace MathNet.Numerics.Distributions
             return "Hypergeometric(N = " + _population + ", M = " + _success + ", n = " + _draws + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="population">The size of the population (N).</param>
+        /// <param name="success">The number successes within the population (K, M).</param>
+        /// <param name="draws">The number of draws without replacement (n).</param>
+        public static bool IsValidParameterSet(int population, int success, int draws)
+        {
+            return population >= 0 && success >= 0 && draws >= 0 && success <= population && draws <= population;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/InverseGamma.cs

@@ -81,6 +81,16 @@ namespace MathNet.Numerics.Distributions
             return "InverseGamma(α = " + _shape + ", β = " + _scale + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="shape">The shape (α) of the distribution. Range: α > 0.</param>
+        /// <param name="scale">The scale (β) of the distribution. Range: β > 0.</param>
+        public static bool IsValidParameterSet(double shape, double scale)
+        {
+            return shape > 0.0 && scale > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/InverseWishart.cs

@@ -87,12 +87,11 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Checks whether the parameters of the distribution are valid.
+        /// Tests whether the provided values are valid parameters for this distribution.
         /// </summary>
         /// <param name="degreesOfFreedom">The degree of freedom (ν) for the inverse Wishart distribution.</param>
         /// <param name="scale">The scale matrix (Ψ) for the inverse Wishart distribution.</param>
-        /// <returns><c>true</c> when the parameters are valid, <c>false</c> otherwise.</returns>
-        static bool IsValidParameterSet(double degreesOfFreedom, Matrix<double> scale)
+        public static bool IsValidParameterSet(double degreesOfFreedom, Matrix<double> scale)
         {
             if (scale.RowCount != scale.ColumnCount)
             {

src/Numerics/Distributions/Laplace.cs

@@ -91,6 +91,16 @@ namespace MathNet.Numerics.Distributions
             return "Laplace(μ = " + _location + ", b = " + _scale + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="location">The location (μ) of the distribution.</param>
+        /// <param name="scale">The scale (b) of the distribution. Range: b > 0.</param>
+        public static bool IsValidParameterSet(double location, double scale)
+        {
+            return scale > 0.0 && !Double.IsNaN(location);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/LogNormal.cs

@@ -124,6 +124,16 @@ namespace MathNet.Numerics.Distributions
             return "LogNormal(μ = " + _mu + ", σ = " + _sigma + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="mu">The log-scale (μ) of the distribution.</param>
+        /// <param name="sigma">The shape (σ) of the distribution. Range: σ ≥ 0.</param>
+        public static bool IsValidParameterSet(double mu, double sigma)
+        {
+            return sigma >= 0.0 && !Double.IsNaN(mu);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/MatrixNormal.cs

@@ -100,13 +100,12 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Checks whether the parameters of the distribution are valid.
+        /// Tests whether the provided values are valid parameters for this distribution.
         /// </summary>
         /// <param name="m">The mean of the matrix normal.</param>
         /// <param name="v">The covariance matrix for the rows.</param>
         /// <param name="k">The covariance matrix for the columns.</param>
-        /// <returns><c>true</c> when the parameters are valid, <c>false</c> otherwise.</returns>
-        static bool IsValidParameterSet(Matrix<double> m, Matrix<double> v, Matrix<double> k)
+        public static bool IsValidParameterSet(Matrix<double> m, Matrix<double> v, Matrix<double> k)
         {
             var n = m.RowCount;
             var p = m.ColumnCount;

src/Numerics/Distributions/Multinomial.cs

@@ -129,14 +129,14 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Checks whether the parameters of the distribution are valid.
+        /// Tests whether the provided values are valid parameters for this distribution.
         /// </summary>
         /// <param name="p">An array of nonnegative ratios: this array does not need to be normalized
         /// as this is often impossible using floating point arithmetic.</param>
         /// <param name="n">The number of trials.</param>
         /// <returns>If any of the probabilities are negative returns <c>false</c>,
         /// if the sum of parameters is 0.0, or if the number of trials is negative; otherwise <c>true</c>.</returns>
-        static bool IsValidParameterSet(IEnumerable<double> p, int n)
+        public static bool IsValidParameterSet(IEnumerable<double> p, int n)
         {
             var sum = 0.0;
             foreach (var t in p)

src/Numerics/Distributions/NegativeBinomial.cs

@@ -83,6 +83,16 @@ namespace MathNet.Numerics.Distributions
             return "NegativeBinomial(R = " + _trials + ", P = " + _p + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="r">The number of failures (r) until the experiment stopped. Range: r ≥ 0.</param>
+        /// <param name="p">The probability (p) of a trial resulting in success. Range: 0 ≤ p ≤ 1.</param>
+        public static bool IsValidParameterSet(double r, double p)
+        {
+            return r >= 0.0 && p >= 0.0 && p <= 1.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Normal.cs

@@ -152,6 +152,16 @@ namespace MathNet.Numerics.Distributions
             return "Normal(μ = " + _mean + ", σ = " + _stdDev + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="mean">The mean (μ) of the normal distribution.</param>
+        /// <param name="stddev">The standard deviation (σ) of the normal distribution. Range: σ ≥ 0.</param>
+        public static bool IsValidParameterSet(double mean, double stddev)
+        {
+            return stddev >= 0.0 && !Double.IsNaN(mean);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/NormalGamma.cs

@@ -143,16 +143,15 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Checks whether the parameters of the distribution are valid.
+        /// Tests whether the provided values are valid parameters for this distribution.
         /// </summary>
         /// <param name="meanLocation">The location of the mean.</param>
         /// <param name="meanScale">The scale of the mean.</param>
         /// <param name="precShape">The shape of the precision.</param>
         /// <param name="precInvScale">The inverse scale of the precision.</param>
-        /// <returns><c>true</c> when the parameters are valid, <c>false</c> otherwise.</returns>
-        static bool IsValidParameterSet(double meanLocation, double meanScale, double precShape, double precInvScale)
+        public static bool IsValidParameterSet(double meanLocation, double meanScale, double precShape, double precInvScale)
         {
-            return (meanScale > 0.0) && (precShape > 0.0) && (precInvScale > 0.0) && !Double.IsNaN(meanLocation);
+            return meanScale > 0.0 && precShape > 0.0 && precInvScale > 0.0 && !Double.IsNaN(meanLocation);
         }
 
         /// <summary>

src/Numerics/Distributions/Pareto.cs

@@ -85,6 +85,16 @@ namespace MathNet.Numerics.Distributions
             return "Pareto(xm = " + _scale + ", α = " + _shape + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="scale">The scale (xm) of the distribution. Range: xm > 0.</param>
+        /// <param name="shape">The shape (α) of the distribution. Range: α > 0.</param>
+        public static bool IsValidParameterSet(double scale, double shape)
+        {
+            return scale > 0.0 && shape > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Poisson.cs

@@ -83,6 +83,15 @@ namespace MathNet.Numerics.Distributions
             return "Poisson(λ = " + _lambda + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="lambda">The lambda (λ) parameter of the Poisson distribution. Range: λ > 0.</param>
+        public static bool IsValidParameterSet(double lambda)
+        {
+            return lambda > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Rayleigh.cs

@@ -83,6 +83,15 @@ namespace MathNet.Numerics.Distributions
             return "Rayleigh(σ = " + _scale + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="scale">The scale (σ) of the distribution. Range: σ > 0.</param>
+        public static bool IsValidParameterSet(double scale)
+        {
+            return scale > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Stable.cs

@@ -88,6 +88,18 @@ namespace MathNet.Numerics.Distributions
             return "Stable(α = " + _alpha + ", β = " + _beta + ", c = " + _scale + ", μ = " + _location + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="alpha">The stability (α) of the distribution. Range: 2 ≥ α > 0.</param>
+        /// <param name="beta">The skewness (β) of the distribution. Range: 1 ≥ β ≥ -1.</param>
+        /// <param name="scale">The scale (c) of the distribution. Range: c > 0.</param>
+        /// <param name="location">The location (μ) of the distribution.</param>
+        public static bool IsValidParameterSet(double alpha, double beta, double scale, double location)
+        {
+            return alpha > 0.0 && alpha <= 2.0 && beta >= -1.0 && beta <= 1.0 && scale > 0.0 && !Double.IsNaN(location);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/StudentT.cs

@@ -111,6 +111,17 @@ namespace MathNet.Numerics.Distributions
             return "StudentT(μ = " + _location + ", σ = " + _scale + ", ν = " + _freedom + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="location">The location (μ) of the distribution.</param>
+        /// <param name="scale">The scale (σ) of the distribution. Range: σ > 0.</param>
+        /// <param name="freedom">The degrees of freedom (ν) for the distribution. Range: ν > 0.</param>
+        public static bool IsValidParameterSet(double location, double scale, double freedom)
+        {
+            return scale > 0.0 && freedom > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Triangular.cs

@@ -89,6 +89,17 @@ namespace MathNet.Numerics.Distributions
             return "Triangular(Lower = " + _lower + ", Upper = " + _upper + ", Mode = " + _mode + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="lower">Lower bound. Range: lower ≤ mode ≤ upper</param>
+        /// <param name="upper">Upper bound. Range: lower ≤ mode ≤ upper</param>
+        /// <param name="mode">Mode (most frequent value).  Range: lower ≤ mode ≤ upper</param>
+        public static bool IsValidParameterSet(double lower, double upper, double mode)
+        {
+            return upper >= mode && mode >= lower && !Double.IsInfinity(upper) && !Double.IsInfinity(lower) && !Double.IsInfinity(mode);
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Weibull.cs

@@ -93,6 +93,16 @@ namespace MathNet.Numerics.Distributions
             return "Weibull(k = " + _shape + ", λ = " + _scale + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="shape">The shape (k) of the Weibull distribution. Range: k > 0.</param>
+        /// <param name="scale">The scale (λ) of the Weibull distribution. Range: λ > 0.</param>
+        public static bool IsValidParameterSet(double shape, double scale)
+        {
+            return shape > 0.0 && scale > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>

src/Numerics/Distributions/Wishart.cs

@@ -87,30 +87,11 @@ namespace MathNet.Numerics.Distributions
         }
 
         /// <summary>
-        /// Sets the parameters of the distribution after checking their validity.
-        /// </summary>
-        /// <param name="degreesOfFreedom">The degrees of freedom (n) for the Wishart distribution.</param>
-        /// <param name="scale">The scale matrix (V) for the Wishart distribution.</param>
-        /// <exception cref="ArgumentOutOfRangeException">When the parameters are out of range.</exception>
-        void SetParameters(double degreesOfFreedom, Matrix<double> scale)
-        {
-            if (Control.CheckDistributionParameters && !IsValidParameterSet(degreesOfFreedom, scale))
-            {
-                throw new ArgumentException(Resources.InvalidDistributionParameters);
-            }
-
-            _degreesOfFreedom = degreesOfFreedom;
-            _scale = scale;
-            _chol = _scale.Cholesky();
-        }
-
-        /// <summary>
-        /// Checks whether the parameters of the distribution are valid.
+        /// Tests whether the provided values are valid parameters for this distribution.
         /// </summary>
         /// <param name="degreesOfFreedom">The degrees of freedom (n) for the Wishart distribution.</param>
         /// <param name="scale">The scale matrix (V) for the Wishart distribution.</param>
-        /// <returns><c>true</c> when the parameters are valid, <c>false</c> otherwise.</returns>
-        static bool IsValidParameterSet(double degreesOfFreedom, Matrix<double> scale)
+        public static bool IsValidParameterSet(double degreesOfFreedom, Matrix<double> scale)
         {
             if (scale.RowCount != scale.ColumnCount)
             {
@@ -133,6 +114,24 @@ namespace MathNet.Numerics.Distributions
             return true;
         }
 
+        /// <summary>
+        /// Sets the parameters of the distribution after checking their validity.
+        /// </summary>
+        /// <param name="degreesOfFreedom">The degrees of freedom (n) for the Wishart distribution.</param>
+        /// <param name="scale">The scale matrix (V) for the Wishart distribution.</param>
+        /// <exception cref="ArgumentOutOfRangeException">When the parameters are out of range.</exception>
+        void SetParameters(double degreesOfFreedom, Matrix<double> scale)
+        {
+            if (Control.CheckDistributionParameters && !IsValidParameterSet(degreesOfFreedom, scale))
+            {
+                throw new ArgumentException(Resources.InvalidDistributionParameters);
+            }
+
+            _degreesOfFreedom = degreesOfFreedom;
+            _scale = scale;
+            _chol = _scale.Cholesky();
+        }
+
         /// <summary>
         /// Gets or sets the degrees of freedom (n) for the Wishart distribution.
         /// </summary>

src/Numerics/Distributions/Zipf.cs

@@ -89,6 +89,16 @@ namespace MathNet.Numerics.Distributions
             return "Zipf(S = " + _s + ", N = " + _n + ")";
         }
 
+        /// <summary>
+        /// Tests whether the provided values are valid parameters for this distribution.
+        /// </summary>
+        /// <param name="s">The s parameter of the distribution.</param>
+        /// <param name="n">The n parameter of the distribution.</param>
+        public static bool IsValidParameterSet(double s, int n)
+        {
+            return n > 0 && s > 0.0;
+        }
+
         /// <summary>
         /// Sets the parameters of the distribution after checking their validity.
         /// </summary>