Tausky, DavidLabahn, GeorgeLank, EdwardMarzouk, MiretteMichiel van de Panne and Eric Saund2014-01-282014-01-282007978-3-905674-00-21812-3503https://doi.org/10.2312/SBM/SBM07/115-122In this paper we describe strategies for recognizing and using hand drawn matrices in a pen math system. This includes a new technique to recognize common short-forms of writing matrices using ellipsis (. . . ). Ellipsis are commonly used in sketched matrices to illustrate the structure of a matrix without fully specifying the matrix. A second contribution of this paper is a new method to estimate the parameters of the hand drawn matrix, such as the number and position of the rows and columns. This is done using a modified clustering algorithm, allowing one to reduce the number of hard-coded constraints.Categories and Subject Descriptors (according to ACM CCS): I.5.4 [Computing Methodologies: Pattern Recognition]: Applications