Category Archives: algorithms

How to tabulate ranked voting in C#

Posted on June 24, 2021 by RodStephens

New York City’s recent election used a ranked voting ballot. This example shows how you might find the winner in a ranked voting election. What Is Ranked Voting? In ranked voting (aka ranked-choice voting or preferential voting), each voter ranks … Continue reading →

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Graph the gamma function in C#

Posted on March 5, 2021 by RodStephens

The post Calculate the gamma function in C# uses numerical integration to calculate the gamma function. (See my book Essential Algorithms, Second Edition for information on numerical integration.) That method works fairly well for calculating Γ(x) where x ≤ 1. … Continue reading →

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Calculate the gamma function in C#

Posted on February 28, 2021 by RodStephens

The gamma function, represented by the capital Greek letter gamma Γ, was derived by Daniel Bernoulli for complex numbers with a positive real part. The interesting thing about the gamma function is that &Gamma(n + 1) = n! for integers … Continue reading →

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Simulate a doubling betting strategy in C#

Posted on February 5, 2021 by RodStephens

Casinos love customers who have a betting strategy because those customers always end up losing. As long as the game’s events are independent of each other (for example, one roll of the dice does not depend on the previous rolls), … Continue reading →

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Use k-means clustering to find clusters of data in C#

Posted on January 26, 2021 by RodStephens

I was recently editing John Mueller and Luca Massaron’s book Machine Learning For Dummies, Second Edition. (This link is for the first edition. I’ll try to remember to update it when the new edition is available.) The book is about … Continue reading →

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Automatically set camera distance in WPF and C#

Posted on January 26, 2021 by RodStephens

This example extends the post Build a geodesic sphere with WPF and C# to let you automatically set the camera distance to make the scene fill the viewport. Making a 3D scene fill the viewport nicely can be tricky. The … Continue reading →

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Enlarge a polygon that has colinear vertices in C#

Posted on December 1, 2020 by RodStephens

The example Enlarge a polygon in C# shows how you can expand a polygon. The basic idea is to offset each of the polygon’s edges away from the polygon’s center and then see where adjacent edges intersect as shown in … Continue reading →

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Overlay parts of images in C#

Posted on September 8, 2020 by RodStephens

My previous post Brighten pixels in an image in C# lets you brighten certain pixels in an image. Unfortunately is often brightens pixels outside of the area that you want to modify. For example, in the left side of the … Continue reading →

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Brighten pixels in an image in C#

Posted on September 7, 2020 by RodStephens

Sometimes when I take a picture, the poor lighting makes some pixels come out less brightly than I would like. For example, in the picture on the right the red raspberries aren’t very red. This example lets you brighten pixels. … Continue reading →

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Perform binary contrast enhancement more quickly in C#

Posted on September 5, 2020 by RodStephens

The example Perform binary contrast enhancement interactively in C# lets you convert an image into completely black and white pixels depending on their brightness. Pixels that are brighter than a given cutoff value are converted into white. Those that are … Continue reading →

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