I am aware that sparse matrices are most effciently worked with when they are created at once from a set of indices and values.
However, due to the size of my data, I am unable to store all indices and values at once, and am forced to batch my execution, so that a sparse matrix is built from a set of indices and values once in a while (say every 100th input file).
This introduces the problem of how to add two sparse matrices, which are not guaranteed to have the same dimension, as I need to accumulate the values (add them) if indices are identical.
I am currently using the ndSparse class from File Exchange, but would also be interested in an answer for MATLAB's built-in sparse function.
The main problem lies in making sure both sparse matrices have the same dimension. Is there any smart/efficient way to do this? Using padarray is not an option.