csr_matrix column index order

[Roman]

Hello Steven!

Please, can you tell about column index order in each row of csr matrix format in cusplibrary. According to the documentation [1]:
"The matrix entries within the same row must be sorted by column index"
Does it has influence on results of algorithms of matrix vector products?


[1] http://cusplibrary.github.io/classcusp_1_1csr__matrix.html#details

[Steven Dalton]

Hello Roman,

 In CSR format the column indices within each row are sorted by the column index. This ordering does not have any impact on some operations, such as sparse matrix-vector multiply, but it is used heavily during the conversion between formats and more complex operations, such as sparse matrix-sparse matrix multiply.

Steve

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[Roman S]

Hello, Steven.

Thank you for your answer. In my application I am collecting a matrix with unsorted column indices in each row. When I compare the resulting matricies collected by the apllication code compiled for the host and  for device they coincides well. But when I try to solve it by gmres method with scaled-bridson preconditioner of cusplibrary, it converges well for host and does not converges for the device compilation of the same code. Does the result may depend on column index order in each row?

25 сент. 2017 г. 16:43 пользователь "Steven Dalton" <sdal...@gmail.com> написал:

[Roman]

Hello Steven,

Is it possible some how to sort a column indices and values of each row of CSR matrix format on the device?

Thank you,
Roman

понедельник, 25 сентября 2017 г., 22:09:02 UTC+3 пользователь Roman написал: