Home File format optimized for sparse matrix exchange
 I want to save a sparse matrix of numbers (integers, but it could be floats) to a file for data exchange. For sparse matrix I mean a matrix where a high percentage of values (typically 90%) are equal to 0. Sparse in this case does not relate to the file format but to the actual content of the matrix. The matrix is formatted in the following way:  col1 col2 .... row1 int1_1 int1_2 .... row2 int2_1 .... .... .... .... .... ....  By using a text file (tab-delimited) the size of the file is 4.2G. Which file format, preferably ubiquitous such as a .txt file, can I use to easily load and save this sparse data matrix? We usually work with Python/R/Matlab, so formats that are supported by these are preferred.