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AI : Neural Network for beginners (Part 2 of 3)

, 29 Jan 2007 181.3K 5.4K 245
AI : An Introduction into Neural Networks (Multi-layer networks / Back Propagation)
using System;
using System.Collections.Generic;
using System.Text;

namespace Backprop_ANN_XOR
    #region SigmoidActivationFunction CLASS
    /// <summary>
    /// Provides a sigmoid activation function
    /// </summary>
    public class SigmoidActivationFunction
        /// <summary>
        /// Takes a value for a current network node, and applies a sigmoid
        /// activation function to it, which is then returned
        /// </summary>
        /// <param name="x">The value to apply the activation to</param>
        /// <returns>The activation value, after a sigmoid function</returns>
        public static double processValue(double x)
            return 1.0 / (1.0 + Math.Pow(Math.E, -x));

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About the Author

Sacha Barber
Software Developer (Senior)
United Kingdom United Kingdom
I currently hold the following qualifications (amongst others, I also studied Music Technology and Electronics, for my sins)

- MSc (Passed with distinctions), in Information Technology for E-Commerce
- BSc Hons (1st class) in Computer Science & Artificial Intelligence

Both of these at Sussex University UK.


I am lucky enough to have won a few awards for Zany Crazy code articles over the years

  • Microsoft C# MVP 2015
  • Codeproject MVP 2015
  • Microsoft C# MVP 2014
  • Codeproject MVP 2014
  • Microsoft C# MVP 2013
  • Codeproject MVP 2013
  • Microsoft C# MVP 2012
  • Codeproject MVP 2012
  • Microsoft C# MVP 2011
  • Codeproject MVP 2011
  • Microsoft C# MVP 2010
  • Codeproject MVP 2010
  • Microsoft C# MVP 2009
  • Codeproject MVP 2009
  • Microsoft C# MVP 2008
  • Codeproject MVP 2008
  • And numerous codeproject awards which you can see over at my blog

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