Add a CSR matrix class

[KyleVaughn]

Description:

Implement a Compressed Sparse Row (CSR) matrix class as part of our sparse matrix library. The CSR format is an efficient storage method for sparse matrices, storing only non-zero elements along with row and column indexing information. This class will serve as a fundamental component for CSR-based matrix operations in our library.

Tasks:

• [ ] Create a new file named csr_matrix.h in the include directory.
• [ ] Define the CSRMatrix class with the following private members:
  • [ ] int nrows: number of rows
  • [ ] int ncols: number of columns
  • [ ] int nnz: number of non-zero elements
  • [ ] std::vector row_ptr: array of row pointers
  • [ ] std::vector col_idx: array of column indices
  • [ ] std::vector values: array of non-zero values
• [ ] Implement a default constructor that initializes an empty CSR matrix.
• [ ] Implement a parameterized constructor that takes the number of rows, columns, and non-zero elements, and initializes the CSR data structures.
• [ ] Implement a copy constructor for deep copying a CSR matrix.
• [ ] Implement a move constructor for efficient transfer of resources.
• [ ] Implement a destructor to properly clean up any dynamically allocated resources (if any).
• [ ] Implement getter methods for accessing private members.
• [ ] Add appropriate comments and documentation for the class and its methods.

Definition of done:

• CSRMatrix class implemented with default, parameterized, copy, and move constructors, and destructor
• Private members properly initialized and managed
• Getter methods implemented for all private members
• Class compiles without errors and passes basic unit tests
• Code adheres to project's coding standards and is well-documented

[shreyasv11]

@NiloyGupta-UM this is ready for review.

[NiloyGupta-UM]

nrows, ncols, and nnz should be of the size_t type rather than standard int. Furthermore, what data types are the row_ptr, col_idx, and values vectors holding? Also, assuming we are sticking with the file conventions already started, the header file should be named SparseMatrix_CSR.hpp. Furthermore, any nontrivial methods should be contained in a .cpp file, so this should also be a specification.

Also, implementing accessor methods has its own issue, so this task should be removed from this issue.

Other than those changes, the list of tasks and requirements is quite comprehensive and seems adequate. A couple of changes might need to be made depending on some of the coding conventions required by the group.