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Euclidean Distance
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The Euclidean distance for real valued features is the square root of the sum of squared disparity between the corresponding feature dimensions of two data points.
.. math::
d({\bf x},{\bf x'})= \sqrt{\sum_{i=0}^{d}|{\bf x_i}-{\bf x'_i}|^2}
where :math:`\bf x` and :math:`\bf x'` are :math:`d` dimensional feature vectors.
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Example
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Imagine we have files with data. We create CDenseFeatures (here 64 bit floats aka RealFeatures) as
.. sgexample:: euclidean.sg:create_features
We create an instance of :sgclass:`CEuclideanDistance` by passing it :sgclass:`CDenseFeatures`.
.. sgexample:: euclidean.sg:create_instance
Distance matrix can be extracted as follows:
.. sgexample:: euclidean.sg:extract_distance
We can use the same instance with new :sgclass:`CDenseFeatures` to compute distance.
.. sgexample:: euclidean.sg:refresh_distance
If desired, squared distance can be extracted like:
.. sgexample:: euclidean.sg:extract_sq_distance
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References
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:wiki:`Euclidean_distance`
.. bibliography:: ../../references.bib
:filter: docname in docnames