diff --git a/src/UnitTests/ArgumentCheckContract.cs b/src/UnitTests/ArgumentCheckContract.cs
new file mode 100644
index 00000000..7779adb9
--- /dev/null
+++ b/src/UnitTests/ArgumentCheckContract.cs
@@ -0,0 +1,119 @@
+// <copyright file="ArgumentCheckContract.cs" company="Math.NET">
+// Math.NET Numerics, part of the Math.NET Project
+// http://mathnet.opensourcedotnet.info
+//
+// Copyright (c) 2009 Math.NET
+//
+// Permission is hereby granted, free of charge, to any person
+// obtaining a copy of this software and associated documentation
+// files (the "Software"), to deal in the Software without
+// restriction, including without limitation the rights to use,
+// copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+// </copyright>
+
+namespace MathNet.Numerics.UnitTests
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Linq.Expressions;
+    using MbUnit.Framework;
+    using MbUnit.Framework.ContractVerifiers;
+
+    internal class ArgumentCheckContract<T> : AbstractContract
+    {
+        public Expression<Func<T>> TypicalUse { get; set; }
+        public Expression<Func<T>>[] TypicalUses { get; set; }
+        public Func<T> BadUse { get; set; }
+        public Func<T>[] BadUses { get; set; }
+
+        protected override IEnumerable<Test> GetContractVerificationTests()
+        {
+            if (TypicalUse != null)
+            {
+                yield return CreateNullArgumentCheckTest(TypicalUse);
+            }
+
+            if (TypicalUses != null)
+            {
+                foreach (var typicalUse in TypicalUses)
+                {
+                    yield return CreateNullArgumentCheckTest(typicalUse);
+                }
+            }
+
+            if (BadUse != null)
+            {
+                yield return CreateBadArgumentCheckTest(BadUse);
+            }
+
+            if (BadUses != null)
+            {
+                foreach (var badUse in BadUses)
+                {
+                    yield return CreateBadArgumentCheckTest(badUse);
+                }
+            }
+        }
+
+        private static Test CreateNullArgumentCheckTest(Expression<Func<T>> typicalUse)
+        {
+            return new TestCase(
+                "NullArgumentCheck " + typicalUse.Body,
+                () =>
+                {
+                    Assert.DoesNotThrow(() => typicalUse.Compile()());
+
+                    // we only support method calls and constructors for now.
+                    if (typicalUse.Body.NodeType != ExpressionType.New
+                        && typicalUse.Body.NodeType != ExpressionType.Call)
+                    {
+                        Assert.Fail(
+                            "Subject '{0}' is neither a constructor or a method call.",
+                            typicalUse.ToString());
+                        return;
+                    }
+
+                    var badUses = typicalUse.ApplySingleMapEachArgument<T>(
+                        t => !t.IsValueType,
+                        e => Expression.Constant(null, e.Type));
+
+                    foreach (var badUse in badUses)
+                    {
+                        var closureBadUseReference = badUse;
+
+                        Assert.Throws(
+                            typeof (ArgumentNullException),
+                            () => closureBadUseReference.Compile()(),
+                            "Subject '{0}' must check for null arguments",
+                            closureBadUseReference.ToString());
+                    }
+                });
+        }
+
+        private static Test CreateBadArgumentCheckTest(Func<T> badUse)
+        {
+            return new TestCase(
+                "BadArgumentCheck " + badUse.Method,
+                () => Assert.Throws(
+                          typeof (ArgumentException),
+                          () => badUse(),
+                          "Subject '{0}' must check for bad arguments",
+                          badUse.ToString()));
+        }
+    }
+}
diff --git a/src/UnitTests/InterpolationTests/FunctionalHelpers.cs b/src/UnitTests/FunctionalHelpers.cs
similarity index 75%
rename from src/UnitTests/InterpolationTests/FunctionalHelpers.cs
rename to src/UnitTests/FunctionalHelpers.cs
index e2d91552..ada4d89c 100644
--- a/src/UnitTests/InterpolationTests/FunctionalHelpers.cs
+++ b/src/UnitTests/FunctionalHelpers.cs
@@ -26,13 +26,11 @@
 // OTHER DEALINGS IN THE SOFTWARE.
 // </copyright>
 
-using System.Collections.Generic;
-using System.Linq.Expressions;
-using MathNet.Numerics.Interpolation;
-
-namespace MathNet.Numerics.UnitTests.InterpolationTests
+namespace MathNet.Numerics.UnitTests
 {
     using System;
+    using System.Collections.Generic;
+    using System.Linq.Expressions;
 
     internal static class FunctionalHelpers
     {
@@ -50,16 +48,24 @@ namespace MathNet.Numerics.UnitTests.InterpolationTests
             return newList;
         }
 
-        internal static IEnumerable<Expression<Func<IInterpolation>>> ApplySingleMapEachArgument(
+        internal static IEnumerable<Expression<Func<T>>> ApplySingleMapEachArgument<T>(
             this LambdaExpression lambda,
             Func<Type, bool> predicate,
             Func<Expression, Expression> replace)
         {
             var body = lambda.Body;
+            var bodyCall = body as MethodCallExpression;
+            var bodyCtor = body as NewExpression;
+
+            if (bodyCall == null && bodyCtor == null)
+            {
+                throw new NotSupportedException();
+            }
+
             var arguments =
-                body is NewExpression
-                    ? ((NewExpression)body).Arguments
-                    : ((MethodCallExpression)body).Arguments;
+                bodyCall != null
+                    ? bodyCall.Arguments
+                    : bodyCtor.Arguments;
 
             for (int i = 0; i < arguments.Count; i++)
             {
@@ -70,13 +76,14 @@ namespace MathNet.Numerics.UnitTests.InterpolationTests
 
                 var mappedArguments = ApplySingleMap(arguments, i, replace);
 
-                yield return Expression.Lambda<Func<IInterpolation>>(
-                    body is NewExpression
-                        ? (Expression)Expression.New(
-                                           ((NewExpression)body).Constructor,
+                yield return Expression.Lambda<Func<T>>(
+                    bodyCtor != null
+                        ? (Expression) Expression.New(
+                                           bodyCtor.Constructor,
                                            mappedArguments)
-                        : (Expression)Expression.Call(
-                                           ((MethodCallExpression)body).Method,
+                        : (Expression) Expression.Call(
+                                           bodyCall.Object,
+                                           bodyCall.Method,
                                            mappedArguments));
             }
         }
diff --git a/src/UnitTests/IntegralTransformsTests/InverseTransformTest.cs b/src/UnitTests/IntegralTransformsTests/InverseTransformTest.cs
index dc663072..436ed383 100644
--- a/src/UnitTests/IntegralTransformsTests/InverseTransformTest.cs
+++ b/src/UnitTests/IntegralTransformsTests/InverseTransformTest.cs
@@ -141,7 +141,7 @@ namespace MathNet.Numerics.UnitTests.IntegralTransformsTests
 
             VerifyIsReversibleReal(
                 0x80,
-                1e-10,
+                1e-9,
                 s => dht.NaiveForward(s, options),
                 s => dht.NaiveInverse(s, options));
         }
diff --git a/src/UnitTests/InterpolationTests/InterpolationInfrastructureContract.cs b/src/UnitTests/InterpolationTests/InterpolationInfrastructureContract.cs
index 45c08c28..3f3cddb0 100644
--- a/src/UnitTests/InterpolationTests/InterpolationInfrastructureContract.cs
+++ b/src/UnitTests/InterpolationTests/InterpolationInfrastructureContract.cs
@@ -112,7 +112,7 @@ namespace MathNet.Numerics.UnitTests.InterpolationTests
                             continue;
                         }
 
-                        var modifiedFactories = factory.ApplySingleMapEachArgument(
+                        var modifiedFactories = factory.ApplySingleMapEachArgument<IInterpolation>(
                             t => !t.IsValueType,
                             e => Expression.Constant(null, e.Type));
 
@@ -148,7 +148,7 @@ namespace MathNet.Numerics.UnitTests.InterpolationTests
                             continue;
                         }
 
-                        var modifiedFactories = factory.ApplySingleMapEachArgument(
+                        var modifiedFactories = factory.ApplySingleMapEachArgument<IInterpolation>(
                             t => !t.IsValueType,
                             e => Expression.Constant(new double[MinimumSampleCount - 1], typeof(double[])));
 
@@ -194,7 +194,7 @@ namespace MathNet.Numerics.UnitTests.InterpolationTests
                             continue;
                         }
 
-                        var modifiedFactories = factory.ApplySingleMapEachArgument(
+                        var modifiedFactories = factory.ApplySingleMapEachArgument<IInterpolation>(
                             t => !t.IsValueType,
                             e =>
                             {
diff --git a/src/UnitTests/UnitTests.csproj b/src/UnitTests/UnitTests.csproj
index 74f53267..003f5f22 100644
--- a/src/UnitTests/UnitTests.csproj
+++ b/src/UnitTests/UnitTests.csproj
@@ -59,6 +59,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="ArgumentCheckContract.cs" />
     <Compile Include="AssertHelpers.cs" />
     <Compile Include="CombinatoricsTests\CombinatoricsCountingTest.cs" />
     <Compile Include="ComplexTests\ComplexTest.cs" />
@@ -74,7 +75,7 @@
     <Compile Include="IntegralTransformsTests\InverseTransformTest.cs" />
     <Compile Include="IntegralTransformsTests\SampleProvider.cs" />
     <Compile Include="IntegrationTests\IntegrationTest.cs" />
-    <Compile Include="InterpolationTests\FunctionalHelpers.cs" />
+    <Compile Include="FunctionalHelpers.cs" />
     <Compile Include="InterpolationTests\InterpolationInfrastuctureTest.cs" />
     <Compile Include="InterpolationTests\InterpolationFunctionalContract.cs" />
     <Compile Include="InterpolationTests\InterpolationInfrastructureContract.cs" />