craigtp

public static class NumericHelpers
    {
        // Float point maths is whack.  We can't check for absolute equality as floating point numbers are imprecise
        // and are subject to rounding issues (See: http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html)
        // Therefore, we can't check for absolute equality, but instead we have to need to check for values being
        // "nearly" equal, which allows a small margin of error (i.e. something known as the "Epsilon" value for
        // the given data type for this CPU that this code is running on).
        public static bool NearlyEqual(double a, double b, double epsilon)
        {
            var absA = Math.Abs(a);

craigtp

gci -recu -inc "*.*" | % { $_.LastWriteTime = Get-Date }

craigtp

Keybase proof

I hereby claim:

• I am craigtp on github.
• I am craigtp (https://keybase.io/craigtp) on keybase.
• I have a public key whose fingerprint is 8FBD 50F4 7D2C E90F 95D6 1B27 3965 4610 07EB B49F

To claim this, I am signing this object:

craigtp

using System;
using System.Security.Cryptography;

namespace BetterRandomNumbers
{
	// BetterRandom.cs
	// This class implements a random number generator that is based off the Windows "Next Generation" cryptographically secure
	// random number generator.  It inherits from the base Random class, so can be used as a "drop-in" replacement for the
	// built-in .NET System.Security.Random class, but providing a superior quality of random numbers.
    public class BetterRandom : Random, IDisposable

craigtp

Value objects are an important concept in DDD. This kata is made both to learn value objects and to learn better ways of testing.

Write a probability value object. It should contain the following methods:
   Probability CombinedWith(Probability)
   Probability InverseOf()
   Probability Either(Probability)

if you forget your probability math:
   Either:P(A) + P(B) - P(A)P(B)
   CombinedWith: P(A)P(B)

craigtp

OK so now you have implemented the kata. Your tests should look something like this:

We can say that the tests define the object "in a calculus of itself".
They are not state based tests, they define how the behaviours of the object interact with each other.

To see the real value of this let's introduce some change ... I hear real system's do this occasionally.
Because this is a high performance system decimal math is too slow. You now need to use floats instead. 

Need help on floating point math? Check out: http://www-users.math.umd.edu/~jkolesar/mait613/floating_point_math.pdf

craigtp

using System;

namespace ShortCodes
{
    public static class ShortCodes
    {
        // You may change the "shortcode_Keyspace" variable to contain as many or as few characters as you
        // please.  The more characters that are included in the "shortcode_Keyspace" constant, the shorter
        // the codes you can produce for a given long.
        private static string shortcodeKeyspace = "abcdefghijklmnopqrstuvwxyz0123456789";

craigtp

# Run this as Administrator
net stop w3svc
Get-ChildItem "C:\Windows\Microsoft.NET\Framework*\v*\Temporary ASP.NET Files" -Recurse | Remove-Item -Recurse -Force
net start w3svc

craigtp

(dir -include *.cs -recurse | select-string .).Count

craigtp

-- Create a temporary table in an in-memory variable simply to allow the
-- select statement to output multiple rows.
DECLARE @TestTable TABLE (uniqueID int)
INSERT INTO @TestTable
SELECT 1 UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL
SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 UNION ALL SELECT 9 UNION ALL SELECT 10

-- The main Select statement that shows different correct (and incorrect) ways to generate
-- "random" things in a set-based select statement.
SELECT