Save sparse matrix as row, column, and value vectors

Question

I have a sparse matrix saved in a mat file. I want to process it in C++ but my library expects the sparse matrix to be represented as three vectors: colIdx (vector of indices of nonzero columns), rowIdx (vector of indices of nonzero rows), and val (vector of values).

How should I go about this? Are there any built-in commands doing similar operations?

Shai · Accepted Answer · 2015-08-24 08:23:17Z

3

find is what you are looking for

[rowIdx colIdx val] = find( myHugeSparseMatrix );

answered Aug 24, 2015 at 8:23

Shai

115k39 gold badges259 silver badges398 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

blazs Over a year ago

I get an error (Out of memory). Any ideas on what to do?

Shai Over a year ago

@user111691 bummer :( you might need to process your matrix in blocks. One block at a time.

Adriaan Over a year ago

@user111691 check mathworks.com/help/matlab/import_export/… Read in part of your data, then export the [rowIdx colIdx val] of Shai's find

Collectives™ on Stack Overflow

Save sparse matrix as row, column, and value vectors

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related