Adjacency structure of the counties in the contiguous United States
Monthly total precipitation (mm) for April 1948 in the contiguous United States
Test if Two 'spam' Objects are (Nearly) Equal
Apply Functions Over Sparse Matrix Margins
Cholesky Factorization for Sparse Matrices
Calculate the determinant of a positive definite Sparse Matrix
Graphially represent the nonzero entries
Lower and Upper Triangular Part of a Sparse Matrix
Basic Linear Algebra for Sparse Matrices
Printing and summarizing sparse matrices
Linear Equation Solving for Sparse Matrices
Combine spam Matrices by Rows or Columns