In document
classification, the classes (and their properties) are known
a priori, and documents are assigned to these classes;
whereas, in document clustering, the number, properties, or
membership (composition) of classes is not known in advance.
Thus, classification is an example of supervised machine
learning and clustering that of unsupervised machine learning
[12]. The well-known classical clustering techniques [3] like
k-means, Agglomerative hierarchical clustering are available
but limited in terms of quality of clusters which leads to the
motivation of the development of quantum inspired clustering
technique, where clusters are computed through the minima of
the potential function of the Schrödinger equation. This
scenario will be discussed in the next section